Mark Elliott 19/05/2024 Mark Elliott 19/05/2024

Biography Marty McFly (Michael J Fox)

Great Scott !!! 2015 ‘the Future’ has been and gone…..But what happened in the Past ?

Read the Biography of Marty McFly ( Michael J Fox) - Biff Tannen ( Tom Wilson) - Lorraine Baines McFly ( Lea Thompson) - Jennifer Park ( Claudia Wells ) ( Elisabeth Shue )

Plus - Biff - George - Jennifer - Loranine

Martin Seamus "Marty" McFly

Marty was born on June 12 1968 in Hill Valley, California to George and Lorraine McFly.

He was the youngest of three children. He had a brother Dave, who was born in 1963, and sister Linda, who was born in 1965, a family of Irish descent. He has an uncle Joey, who is serving a prison sentence in 1985 and been denied parole again.

There is an implication that Marty is ashamed of his family and does not spend much time at home, preferring to hang out with Doc, Jennifer, or the guys in his band, The Pinheads.

However, Marty's relationships with his family changed after he returns from 1955, with him no longer being alienated by his parents and his father working as a local college professor and a successful novelist in the alternate timeline he inadvertently created.

Marty also meets his great-great paternal grandparents Seamus and Maggie, when he was stranded in 1885. He also meets their infant son William, Marty's great grandfather.

Seamus and Maggie McFly.png — Seamus and Maggie McFly

Through his interaction with Seamus and Maggie, Marty discovers that Seamus had a brother named Martin, thus Marty's great-great granduncle.

By 2015, Marty has married his girlfriend Jennifer and has two children, Martin "Marty" Jr. and Marlene.

Little is known about Marty's life prior to the first Back to the Future film, except for the fact that he set fire to the living-room rug when he was 8 years old (in a statement of Marty's to his future parents).

He met his friend Dr. Emmett "Doc" Brown when he was around fourteen after hearing that Brown was a dangerous lunatic. Marty, being the “red-blooded American teenager” he was, wanted to go see what it was all about for himself.

Marty McFly and Doc Brown.png — Marty McFly and Doc Brown

He found Doc’s lab and was fascinated by all his inventions. When Doc caught him, he was glad to have someone who liked his work and their friendship started there

Marty met his future girlfriend Jennifer Parker in elementary school, although they became more acquainted after the fourth grade.

Screen Shot 2021-02-09 at 18.03.49.png — Jennifer Parker and Marty McFly

When Marty was fifteen, he sneaked out of the house one evening and set off on his skateboard to meet his friends. However, his mother heard the sound of the skateboard and went after Marty in the car.

At some point, Marty became acquainted with Douglas J. Needles, who would frequently goad him into doing foolish things.

In 1985, Marty plays guitar with his group The Pinheads and likes listening to Huey Lewis and the News, Tom Petty and the Heartbreakers, and Van Halen. Eventually, Marty became the lead guitar player of his band and dreamed of one day becoming a rich and famous rockstar.

Pinheads Back to the Future.png — Pinheads Back to the Future

He is also a talented skateboarder and proves to be an excellent pistol shot, a skill he has honed by endlessly playing shooting games such as Wild Gunman at his local 7-Eleven.

Marty is a friendly, easy going but accident-prone everyman who can sometimes lack critical thinking skills; he is nevertheless brave in the face of danger and can be very quick-witted and intelligent.

He has shown some good and basic street fighting skills and often throws punches in hand-to-hand confrontations.

He is loyal to his family and friends, regardless of whether or not he is estranged from them. His major character flaw is his pride, which causes him to take unnecessary risks to show others that he is not a chicken.

However, during a visit in 1885, when his ancestor Seamus McFly mentions that his brother Martin was killed in an argument after someone questioned his bravery, Marty begins to re-think his stance on what other people think of him.

By 2015, Marty's life has spiraled out of control due to long-term pain from a hand injury that leaves him unable to play guitar.

2015 Marty McFly struggling to play guitar

This injury occurs in 1985, after Marty accepts school enemy Douglas J. Needles' challenge to a road race after being labeled a chicken and crashes into a Rolls-Royce.

In 1885, Biff Tannen's great-grandfather Buford goads Marty into a showdown, which Marty wins despite refusing to draw a gun against Buford. Once he returns to 1985, he remembers both this event and Seamus' advice and politely declines Needles' challenge, avoiding the collision that would have ruined his musical talents.

Back to the Future Rolls Royce incident 1.png — Rolls Royce Incident

This event shows newfound maturity as he often loses his temper when called a chicken. Over the years, Marty learns how to make his decisions on his own terms instead of being influenced by others, thereby changing his future for the better.

MEETING DOC BROWN

On October 2, 1982, Marty was playing his guitar in his garage when he was suddenly confronted by Needles and his gang, who wished to "borrow" Marty's interocitor tube.

Needles was scheduled to play with his band, The Tabascos, that night. However, he had blown the interocitor tube in his guitar amplifier.

Marty was willing to rent his interocitor tube to Needles for $5.00, but Needles replied that he would pay tomorrow when he would bring the tube back. However, Marty accidentally caused Needles to drop the tube when he forcefully grabbed Needles' arm and insisted to be payed upfront.

Marty was then told by Needles that he had to get him a new tube and bring it to the clocktower by four o'clock, or else Needles would beat him up.

Marty was initially hesitant to agree, citing his lack of money and unwillingness to steal. However, he agreed when Needles goaded him by calling him "chicken". Needles then took Marty's guitar and told him he'd give it back when he got him a new tube.

Marty went to a music store and tried to buy one, but was told by the shop attendant that all of the stock was sold to ELB Enterprises. Marty left to go to Dr. Brown's garage to ask for one, but the attendant warned him that Dr. Brown was a real nut case.

Dr. Brown set a series of traps which Marty had to overcome to gain entrance to the garage. After getting an electrical shock after using the keypad on the electrified gate around the garage, a recording stated that he was not "one to foresee" that happening.

Realizing that the wording was unusual, Marty picked up that it was a code, and punched in 1-2-4-C on the keypad. He tried to knock on the door, but no-one answered.

After deciding not to break the window, he attempted to find more clues and found a key underneath an unusual KNOW ENTRY sign. Once inside, he set off elaborately set up a series of objects that caused a chain reaction resulting in him being captured in a net. He pushed his skateboard at the reset switch, which then released the net.

Marty's first meeting with Doc Brown

Einstein, Dr. Brown's dog, then playfully jumped up on Marty, and Dr. Brown himself then entered to greet his guest. He told Marty to call him Doc, as in "What's up, Doc!", and asked him if he was here to apply for the assistant position that he said he had advertised.

Marty told him that he had, and Doc told him that he was impressed that he made his way through the traps, especially his decision to release the net with his skateboard.

Marty then admitted that he hadn't come to apply for a job, but had instead come for an interocitor tube. After Marty assured him that he hadn't intended to rob him, Doc admitted that he had never put out an advertisement for an assistant, but offered Marty the job anyway.

Doc told Marty that he threw out all of the tubes, as he only wanted the box for his Static-O-Matic electric hair chair. Marty then grabbed the tubes out of the trashcan, and went back to Needles.

He gave Needles one of the tubes, and told him that he had stolen the tube from Dr. Emmett Brown. This resulted in Needles being scared, as he knew that Emmett Brown worked on the atomic bomb, and there were rumors that he was radioactive.

Aliases

Marty has had many aliases through the Back to the Future series, usually due to encountering his relatives at some point, such as Lorraine mistakenly thinking his name is "Calvin Klein", due to it being Marty's brand of underwear.

Calvin Klein AKA Marty McFly.png — Calvin Klein aka Marty McFly

In the first film, Marty uses the alias of "Darth Vader, an extraterrestrial from the Planet Vulcan" while wearing a radiation suit in an attempt to coerce George into asking Lorraine out to the dance.

Marty McFly as Darth Vader.png — Marty McFly as Darth Vader

In Part III, Marty uses the name "Clint Eastwood" when asked by Maggie McFly and later by Buford Tannen. In Back to the Future: The Game, he uses one of the three aliases; "Sonny Crockett", "Harry Callahan", and "Michael Corleone".

Clint Eastwood (Marty McFly).png — Marty Marty as Clint Eastwood

Marty McFly as Clint Eastwood.png — Marty McFly as Clint Eastwood

Biff Howard Tannen

Is a fictional character in the Back to the Future trilogy. Thomas F. Wilson plays Biff in all three films as well as the Universal Studios ride, and voiced the character in the animated series.

Biff is the main antagonist of the first and second films. Biff's great-grandfather, Buford "Mad Dog" Tannen, fills a similar role in the third.

The character is portrayed as a tall, aggressive, dim-witted and misogynistic bully who obtains what he wants by intimidating others into doing his work for him, or by cheating.

He and his family members are shown to misuse idioms in ways that make them appear stupid and pathetic despite their intention to insult or scare. His favorite insult is "butthead".

The character of Biff is developed with a history that he was born in Hill Valley, California.

He is identified as the great-grandson of Buford "Mad Dog" Tannen, son of Irving “Kid” Tannen and grandfather of Griff Tannen.

Rather than studying in high school, he is depicted as preferring to bully George McFly into doing his homework for him while he drinks and hangs out with his friends.

Feared by most of his schoolmates, he is less brave without his gang (Match, Skinhead, and 3-D). The only person at Hill Valley High school that Biff is depicted as being afraid of, is Mr. Strickland.

Biff had been living with his grandmother, Gertrude Tannen, at 1809 Mason Street for some time by November 1955. In 1955, Biff was depicted as frequently having been seen driving his black 1946 Ford Deluxe convertible around Hill Valley.

Biffs Relationships

In 1955, Biff had a crush on Lorraine Baines who does not return the sentiments. In the original 1985, Biff's marital status is unknown as no mention of a wife was ever made in the trilogy.

The alternate 1985 reveals that Lorraine, widowed after the murder of George McFly, ended up marrying Biff, in 1973, so that her children could live a better life.

In a video clip after their wedding, Biff is asked, “how does it feel?”, to which he replies, “Third time's the charm.” Hence, it stands to reason, that in the original timeline, Biff would have been married (and perhaps divorced) at least once and presumably, twice before.

Biff's children

By 2015, Biff has a teenage grandson, Griff, suggesting that Biff had at least one child by 1985. The animated series reveals that Biff has a son, Biff Jr.

George McFly

Was born on April 1, 1938 in Hill Valley, California. He was the only child of Arthur McFly and his Canadian-born wife Sylvia Miskin, who were living on Sycamore Street as of 1955.

His parents Arthur McFly and Sylvia Miskin were married in 1936. He was also the grandson of William McFly the first member of the McFly family to be born in the United States.

When he was 12, he nearly stood up for a friend, Billy Stockhausen, who was being bullied, but did not and has hated himself for it ever since.

In 1954, he tried reading How to Win Friends and Influence People, but the advice he gained from this book made people stay away from him even more — with the exception of Biff who, on their first encounter at high school, rubbed a hero sandwich in George's face.

George was probably bullied from a very early age, not just by Biff but by other classmates such as Mark Dixon and even by some adults including Stanford S. Strickland

He had been attracted to Lorraine for some time by 1955 (they may have met for the first time upon entering high school) but was too scared to ask her out.

Original 1955

George watching Lorraine get undressed, before getting hit by her father's car.

On November 5, 1955, George and Lorraine fell in love, when Sam knocked George over in his car due to George falling out of a tree into the road (he had been "birdwatching", watching Lorraine get undressed from the tree).

The Baines family took George into the house and Lorraine felt sorry for him. In a "Florence Nightingale" effect, she fell in love with him and they had their first date a week later, at the Enchantment Under the Sea dance.

George had been considering college but waited until the deadline to decide whether or not to send in the application. He knew his father would talk him out of it, so he likely gave up.

Original 1985

George in 1985 before history was rewritten

George and Lorraine were married on December 7, 1958, and moved into Lyon Estates, their first child Dave was born in 1963 . followed by Linda McFly in 1966 and Marty in 1968.

Despite these changes, By 1985, George stayed much the same as he was when he was 17.

He was dominated by his now supervisor Biff, most of his colleagues and even his neighbours and even kept the same hair styler.

George did not develop the courage to stand up for himself or even for his wife, which depressed her so much that she became an alcoholic, a smoker and overweight. The story of George's life would be rewritten when Marty traveled back into the past.

JENNIFER PARKER

Claudia Wells

Biographical information

Date of birth October 29, 1967

Age (1955) - Not yet born - Age (1985) 17/18 - Age (2015) - 47/48 - Age (2045) - 77/78

Physical description

Gender Female

Hair colour : Brown (Part 1), Red (Parts 2/3), Blonde (Series), Black/Pink/Blonde (Game)

Eye colour :Brown – (Green (Game)

Behind-the-scenes information

Played by

Claudia Wells (Part 1) - Elisabeth Shue (Parts 2/3)

"Jennifer was terrific, of course. He [Marty] was quite taken by her, even felt that he "loved" her in the most adult sense. She was beautiful and fun to be around and she loved his music. Yet somehow she was not quite as important to Marty as the musical experience.

Perhaps in time she would grow to be vastly more valuable to him, but for the moment Jennifer was of this world and his music was of the next. " —From Back to the Future by George Gipe (quote, page 5)

"Marty, one rejection isn't the end of the world."

—Jennifer to Marty after his audition

"How about a ride, Mister?"

—Jennifer to Marty after he returns from 1955.

Jennifer Jane Parker McFly was the girlfriend, and later the wife, of Marty McFly.

Jennifer was the world's fourth time traveler and the third human one. She was the daughter of Danny Parker Jr. and Betty Parker, and the granddaughter of Danny Parker and his wife Betty Lapinski.

Jennifer in Time Machine.png — Jennifer in DeLorean Time Machine

Jennifer and Marty seemed to be "serious" enough for him to introduce her to his best friend, local inventor Dr. Emmett Brown, whom she first regarded as eccentric and strange.

Jennifer is mostly a positive person, knowing what to say to Marty if he needed cheering up, and wondering what happy life she might have in the future.

Biography

Jennifer was born in 1967 in Hill Valley, California. She was Marty's girlfriend, having met him at Hill Valley High School, which they both attended in 1985.

Sometime before 1985, Jennifer met Marty and started dating him, eventually falling passionately in love with him. She also became friends with Doc.

Lorraine Baines McFly

Biographical information

Date of birth : 1938 - Age (1885) - Age (1955) 17 - Age (1985) 47 - Age (2015) 77 - Age (2045) 107

Physical description

Gender : Female

Hair colour : Dark Brown (in 1955/1985), Blonde/grey (in 1985A/2015)

Eye colour : Brown

Behind-the-scenes information

Played by Lea Thompson

"On Marty's right [at the dinner table] was dear old Mom, who was once very attractive and bright. Now, at forty-seven, she was overweight, drank more than was good for her and had more food on her plate than anyone else."— From Back to the Future by George Gipe (quote, page 34)

"Your father kissed me for the very first time on that dance floor." —Lorraine to Marty and Linda

"Biff! Leave him ALONE! Let him go! Let him go!" —Lorraine furiously trying to help George McFly, by attempting to pry an attacking Biff off the latter.

Lorraine Baines McFly

Is the mother of Dave, Linda and Marty McFly and the wife of George McFly. Lorraine liked the attention of boys when she was in school, and lots of them were attracted to her, including both George McFly and Biff Tannen.

Lorraine was not afraid to get what she wanted and often parked in cars with them. Lorraine could stand up for herself and the people she cared about, yet despite this she liked her men to be strong and able to protect her.

She liked thinking back to the "old days", often telling the story of how she originally met and fell in love with George. Lorraine liked to play tennis with her husband and they have been tennis club champions for the past six years by 1985. Lorraine's best friends at school were Betty and Babs, and she could often be found in Lou's Cafe gossiping with them.

Lorraine, aged 17, in 1955

Lorraine Baines was born in 1938 in Hill Valley, California, the eldest child of Sam and Stella Baines. She had five younger siblings: Milton (born 1943), Sally (born 1949), Toby (born 1951), Joey (born 1954), and Ellen (born 1956).

When Lorraine was in elementary school, she witnessed Biff Tannen punching George McFly, and told a teacher, Miss Hodges, about it.

She threatened to send him to a military school in Idaho, but a young teacher named Stanford S. Strickland intervened.

He believed that Biff could be reached with understanding and guidance, but he was proven wrong and later became a very hardened and strict discipliner.

Little else is known about Lorraine's life prior to 1955. What is known is that she had been smoking and drinking for a while, and had "parked" in cars with several boys.

As such, George was probably not her first boyfriend, Lorraine also caught the attention of local bully Biff Tannen but she never took a liking to him.

Original 1955 to 1985

Lorraine, aged 47, in 1985 before the history was changed

Lorraine originally met George McFly on November 5, 1955, when her father Sam Baines almost ran him over with his car. She felt sorry for him, before falling in love with him.

They had their first date a week later at the Enchantment Under the Sea Dance at school, which happened the same day as the famous Hill Valley Thunderstorm.

Back to the Future Prom Photo.png — Back to the Future Prom Photo

Lorraine originally had an addiction to alcohol, which she developed as a teenager and carried into her adulthood.

Lorraine and George married on December 7, 1958, and moved into Lyon Estates where they had three kids, Dave in 1963, Linda in 1965 and Marty in 1968.

By 1985, she was depressed at how her husband could not stand up for her or himself infront of people like Biff, she had also turned to tobacco smoking and drinking alcoholic beverages on an everyday habit.

She would always tell her children not to park in cars with members of the opposite sex, under the false pretense that she never did that when she was their age.

Altered history

George and Lorraine before the kiss.

Her life changed in 1955 when "Calvin Klein" showed up in town. Unaware it was her future son Marty, who had traveled back in time in the DeLorean time machine and had accidentally interfered with her first meeting with George, as Marty had pushed George out of the way of her father's car and George ran away with his bike.

She developed a crush on him. Marty knew he had to get his parents together to prevent himself, as well as his elder siblings, from being erased from existence.

Calvin Klein aja Marty McFly and Lorraine

"He's a dream!" —Lorraine Baines about Calvin Klein (Marty)

After finding out that Lorraine wanted a man who would stand up for her and protect her, these being qualities which George lacked, he came up with a plan where he would pretend to take advantage of Lorraine at the Dance, and the wimpy George would "rescue" her from him.

Marty was shocked when he found that Lorraine liked parking in cars with boys as, in 1985, Lorraine had told him that she found it terrible when girls did so.

Lorraine noticed that Marty was nervous and told him not to be in the situation of dating. Lorraine then kisses him incestuously, much to Marty's shock.

However, Lorraine stops kissing him on the sudden realization that the kiss somehow felt wrong. While still unaware of who Marty truly was, Lorraine said that it did not make sense and it felt as if she was kissing one of the men of her family, such as her grandfather or one of her brothers.

Marty clarifies her reasons of the kiss feeling wrong, assuring her that his feelings for her are purely platonic. Unfortunately, or perhaps fortunately, Biff Tannen showed up instead and tried to force his affection on Lorraine.

Biff's underlings overpowered Marty, hitting him then forcing him into the trunk of a car. Immediately afterwards, George arrived, and delivered his rehearsed lines for Marty not to get fresh.

George was then shocked that the faked rescue had become real. Biff ordered George to beat it. George was about to do so, but momentarily remembered a lesson in "standing tall" from a soda jerk at Lou's Cafe.

George then stated (albeit shakily) "No Biff, you beat it. You leave her alone!" This enraged Biff to the point he then grabbed George's left hand. After initially being overpowered, George's grimace of pain turned to one of anger when he saw a laughing Biff knock Lorraine to the ground when she tried to help him.

An enraged George clenched his free hand into a fist, then bashed Biff in the face, knocking him out, and Lorraine fell in love with the newly-confident George. They kissed for the first time that night and history was back on track. By 1985, she was much healthier and happier than she had been in the original 1985.

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Mark Elliott 11/05/2024 Mark Elliott 11/05/2024

Time Paradox Explained - Back to the Future

Great Scott !!! We feature Doc Brown’s Time Travelling DeLorean in our Blog about one of the wonders of Time Travel the Time Paradox. What is a Time Paradox - How does it relate to Time Travel and we discuss the science involved.

“Doc: “I foresee two possibilities. One, seeing herself thirty years in the future would put Jennifer into shock and she’d simply pass out. Or two, the encounter could create a time paradox. The results of which could cause a chain reaction that would unravel the very fabric of the space-time continuum and destroy the entire universe!... Granted, that’s the worst-case scenario. The destruction however might be limited merely to our own galaxy.”
Marty: “Well that’s a relief!”
— Doc and Marty discussing the implications of 1985 Jennifer running into her 2015 self.
A paradox, in time travel, is “a situation in which the effect of an incident contradicts or eliminates the cause of that same incident”.[1]
”

— https://backtothefuture.fandom.com/wiki/Paradox

Time travel paradox Explained

The Earth rotates around the sun - the sun rotates around the galaxy - the galaxy moves in the universe. All that being said, if the time machine were possible, the DeLorean would be in a different place, and not the same place each time it moves into the past or future.

Here’s one possible answer: The time machine is still affected by the gravitation pull of a body such as that on Earth.
Expounding upon that: Views from inside the time machine indicate that the DeLorean time machine is traveling through a portal that only opens when the machine reaches 88 miles per hour.
Since time travel hasn't been witnessed, it's plausible that the unopened time portals are held in place by the Earth's gravity or by a physical force not yet proven. The ideas behind the first paragraph, about Earth's movement in space, have been discussed in the article about spatial displacement.

Behind the scenes

The word "paradox" is often used to describe a mystery or an unanswered question. eg :
Paradox was also the title of the musical score played during the scene in Part II in which the time-traveling Doc Brown talked with his younger self while handing himself a wrench to attach the electrical cable to the lamppost in 1955; since Doc Brown caused a "pair o' Docs" to occur.

Though many paradoxes arise in the trilogy, Doc may be overzealous about them because, though the effects obviously happen, the risk of destroying the space-time continuum may not really exist, mearly being a fabrication of Doc's mind to give reason to fix time-lines.

Evidence of such exists, because 1985 Doc was willing to correct 1955 Doc with the wrench size and give him the suggestion that he was conducting a weather experiment as well as telling him there was going to be a storm. He also gave 1955 Doc information on how to repair the DeLorean, via the letter, while he was stuck in 1885, knowing the risks.

There is nothing in Einstein’s theories of relativity to rule out time travel, although the very notion of traveling to the past violates one of the most fundamental premises of physics, that of causality.

With the laws of cause and effect out the window, there naturally arises a number of inconsistencies associated with time travel, and listed here are some of those paradoxes which have given both scientist and time travel movie buffs alike more than a few sleepless nights over the years.

The time travel paradoxes which follow fall into two broad categories:

1) Closed Causal Loops, such as the Predestination Paradox and the Bootstrap Paradox, which involve a self-existing time loop in which cause and effect run in a repeating circle, but is also internally consistent with the timeline’s history.

2) Consistency Paradoxes, such as the Grandfather Paradox and other similar variants such as The Hitler paradox, and Polchinski’s Paradox, which generate a number of timeline inconsistencies related to the possibility of altering the past.

1: Predestination Paradox

A Predestination Paradox occurs when the actions of a person traveling back in time becomes part of past events, and may ultimately causes the event he is trying to prevent to take place.

This results in a ‘temporal causality loop’ in which (Event 1) in the ‘past’ influences (Event 2) in the ‘future’ (time travel to the past) which then causes (Event 1) to occur.

With this circular loop of events ensuring that history is not altered by the time traveler, and that any attempts to stop something from happening in the past, will simply lead to the cause itself, instead of stopping it.

This paradox suggests that things are always destined to turn out the same way, and that whatever has happened must happen.

Sound complicated? …… O.K this may sound a grim, but just for a moment Imagine that your lover dies in a hit-and-run car accident, and you travel back in time to save her from her fate, only to find that on your way to the accident you are the one who accidentally runs her over.

Your attempt to change the past has therefore resulted in a predestination paradox. One way of dealing with this type of paradox is to assume that the version of events you have experienced are already built into a self-consistent version of reality, and that by trying to alter the past you will only end up fulfilling your role in creating an event in history, not altering it.

– Cinema Treatment

In ‘The Time Machine’ Movie' in (2002) for instance, Dr. Alexander Hartdegen witnesses his fiancee being killed by a mugger, leading him to build a time machine to travel back in time to save her from her fate.

His subsequent attempts to save her fail, though, leading him to conclude that “I could come back a thousand times… and see her die a thousand ways.” After then traveling centuries into the future to see if a solution has been found to the temporal problem, Hartdegen is told by the Über-Morlock:

“You built your time machine because of Emma’s death. If she had lived, it would never have existed, so how could you use your machine to go back and save her? You are the inescapable result of your tragedy, just as I am the inescapable result of you.”

Movies: Examples of predestination paradoxes in the movies include :

12 Monkeys (1995), TimeCrimes (2007), The Time Traveler’s Wife (2009), and Predestination (2014).

Books: An example of a predestination paradox in a book is Phoebe Fortune and the Pre-destination Paradox by M.S. Crook.

2: Bootstrap Paradox

A Bootstrap Paradox is a type of paradox in which an object, person, or piece of information sent back in time results in an infinite loop where the object has no discernible origin, and exists without ever being created.

It is also known as an Ontological Paradox, as ontology is a branch of philosophy concerned with the nature of being, or existence.

– Information: George Lucas traveling back in time and giving himself the scripts for the Star War movies which he then goes on to direct and gain great fame for would create a bootstrap paradox involving information, as the scripts have no true point of creation or origin.

– Person: A bootstrap paradox involving a person could be, say, a 20 year old male time traveler who goes back 21 years, meets a woman, has an affair, and returns home three months later without knowing the woman was pregnant. Her child grows up to be the 20 year old time traveler, who travels back 21 years through time, meets a woman, and so on.

These ontological paradoxes imply that the future, present and past are not defined, thus giving scientists an obvious problem on how to then pinpoint the “origin” of anything, a word customarily referring to the past, but now rendered meaningless.

Further questions arise as to how the object/data was created, and by whom. Nevertheless, Einstein’s field equations allow for the possibility of closed time loops, with Kip Thorne the first theoretical physicist to recognize traversable wormholes and backwards time travel as being theoretically possible under certain conditions.

Movies: Examples of bootstrap paradoxes in the movies include ‘Somewhere in Time’ (1980), ‘Bill and Ted’s Excellent Adventure’ (1989), ‘The Terminator’ movies, and ‘Time Lapse’ (2014). The Netflix series Dark (2017-19) also features a book called ‘A Journey Through Time’ which presents another classic example of a bootstrap paradox.

Books: Examples of bootstrap paradoxes in books include Michael Moorcock’s ‘Behold The Man’, Tim Powers’ The Anubis Gates, and Heinlein’s “By His Bootstraps”

3: Grandfather Paradox

The Grandfather Paradox concerns ‘self-inconsistent solutions’ to a timeline’s history caused by traveling back in time. For example :

Again we are going to be very grim for a minuet, if you traveled to the past and killed your grandfather, you would never have been born and would not have been able to travel to the past – a paradox. Let’s say you did decide to kill your grandfather because he created a dynasty that ruined the world. You figure if you knock him off before he meets your grandmother then the whole family line (including you) will vanish and the world will be a better place. According to theoretical physicists, the situation could play out as follows:

– Time line protection hypothesis: You pop back in time, walk up to him, and point a revolver at his head. You pull the trigger but the gun fails to fire. Click! Click! Click! The bullets in the chamber have dents in the firing caps. You point the gun elsewhere and pull the trigger. Bang! Point it at your grandfather.. Click! Click! Click! So you try another method to kill him, but that only leads to scars that in later life he attributed to the world’s worst mugger. You can do many things as long as they’re not fatal until you are chased off by a policeman.

– Multiple universes hypothesis: You pop back in time, walk up to him, and point a revolver at his head. You pull the trigger and Boom! The deed is done. You return to the “present” but you never existed here. Everything about you has been erased, including your family, friends, home, possessions, bank account, and history. You’ve entered a timeline where you never existed. Scientists entertain the possibility that you have now created an alternate timeline or entered a parallel universe.

Movies: Example of the Grandfather Paradox in movies include ‘Back to the Future’ (1985), ‘Back to the Future Part II’ (1989), and ‘Back to the Future Part III’ (1990).

Books: Example of the Grandfather Paradox in books include Dr. Quantum in the Grandfather Paradox by Fred Alan Wolf, The Grandfather Paradox by Steven Burgauer, and Future Times Three (1944) by René Barjavel, the very first treatment of a grandfather paradox in a novel.

4: Let’s Kill Hitler Paradox

We will steer off this subject soon but similar to the Grandfather Paradox which paradoxically prevents your own birth, the Killing Hitler paradox erases your own reason for going back in time to kill him. Furthermore, while killing Grandpa might have a limited “butterfly effect”, killing Hitler would have far-reaching consequences for everyone in the world, even if only for the fact you studied him in school.

The paradox itself arises from the idea that if you were successful, then there would be no reason to time travel in the first place. If you killed Hitler then none of his actions would trickle down through history and cause you to want to make the attempt.

Movies/Shows: By far the best treatment for this notion occurred in a ‘Twilight Zone’ episode called ‘Cradle of Darkness’ that sums up the difficulties involved in trying to change history, with another being an episode of Dr Who called ‘Let’s Kill Hitler’.

Books: Examples of the Let’s Kill Hitler Paradox in books include How to Kill Hitler: A Guide For Time Travelers by Andrew Stanek, and the graphic novel I Killed Adolf Hitler by Jason.

5: Polchinski’s Paradox

American theoretical physicist Joseph Polchinski proposed a time paradox scenario in which a billiard ball enters a wormhole, and emerges out the other end in the past just in time to collide with its younger version and stop it going into the wormhole in the first place.

Polchinski’s paradox is taken seriously by physicists, as there is nothing in 'Einstein’s General Relativity to rule out the possibility of time travel, closed time-like curves (CTCs), or tunnels through space-time.

Furthermore, it has the advantage of being based upon the laws of motion, without having to refer to the indeterministic concept of free will, and so presents a better research method for scientists to think about the paradox.

When Joseph Polchinski proposed the paradox, he had Novikov’s Self-Consistency Principle in mind, which basically states that while time travel is possible, time paradoxes are forbidden.

However, a number of solutions have been formulated to avoid the inconsistencies Polchinski suggested, which essentially involves the billiard ball delivering a blow which changes its younger version’s course, but not enough to stop it entering the wormhole.

This solution is related to the ‘timeline-protection hypothesis’ which states that a probability distortion would occur in order to prevent a paradox from happening. This also helps explain why if you tried to time travel and murder your grandfather, something will always happen to make that impossible, thus preserving a consistent version of history.

Books: Paradoxes of Time Travel by Ryan Wasserman is a wide-ranging exploration on the topic of time travel, including Polchinski’s Paradox.

Lets see this in a video

Are Self-fulfilling Prophecies Paradoxes?

A self-fulfilling prophecy is only a causality loop when the prophecy is truly known to happen and events in the future cause effects in the past, otherwise the phenomenon is not so much a paradox as a case of cause and effect.

Say, for instance, an authority figure states that something is inevitable, proper, and true, convincing everyone through persuasive style. People, completely convinced through rhetoric, begin to behave as if the prediction were already true, and consequently bring it about through their actions. This might be seen best by an example where someone convincingly states:

“High-speed Magnetic Levitation Trains will dominate as the best form of transportation from the 21st Century onward.”

Jet travel, relying on diminishing fuel supplies, will be reserved for ocean crossing, and local flights will be a thing of the past. People now start planning on building networks of high-speed trains that run on electricity. Infrastructure gears up to supply the needed parts and the prediction becomes true not because it was truly inevitable (though it is a smart idea), but because people behaved as if it were true.

It even works on a smaller scale – the scale of individuals. The basic methodology for all those “self-help” books out in the world is that if you modify your thinking that you are successful (money, career, dating, etc.), then with the strengthening of that belief you start to behave like a successful person. People begin to notice and start to treat you like a successful person; it is a reinforcement/feedback loop and you actually become successful by behaving as if you were.

Are Time Paradoxes Inevitable?

The Butterfly Effect is a reference to Chaos Theory where seemingly trivial changes can have huge cascade reactions over long periods of time. Consequently, the Timeline corruption hypothesis states that time paradoxes are an unavoidable consequence of time travel, and even insignificant changes may be enough to alter history completely.

Lets explain this theory in a little story ….

A paleontologist, with the help of a time travel device, travels back to the Jurassic Period to get photographs of Stegosaurus, Brachiosaurus, Ceratosaurus, and Allosaurus amongst other dinosaurs. He knows he can’t take samples so he just takes magnificent pictures from the fixed platform that is positioned precisely to not change anything about the environment.

His assistant is about to pick a long blade of grass, but he stops him and explains how nothing must change because of their presence. They finish what they are doing and return to the present, but everything is gone. They reappear in a wild world with no humans, and no signs that they ever existed..

They fall to the floor of their platform, the only man-made thing in the whole world, and lament “Why? We didn’t change anything!” And there on the heel of the scientist’s shoe is a crushed butterfly.

The Butterfly Effect is also a movie, starring Ashton Kutcher as Evan Treborn and Amy Smart as Kayleigh Miller, where a troubled man has had blackouts during his youth, later explained by him traveling back into his own past and taking charge of his younger body briefly. The movie explores the issue of changing the timeline and how unintended consequences can propagate.

Solutions

Scientists eager to avoid the paradoxes presented by time travel have come up with a number of ingenious ways in which to present a more consistent version of reality, some of which have been touched upon here, including:

–The Solution: time travel is impossible because of the very paradox it creates.

–Self-healing hypothesis: successfully altering events in the past will set off another set of events which will cause the present to remain the same.

–The Multiverse or “many-worlds” hypothesis: an alternate parallel universe or timeline is created each time an event is altered in the past.

–Erased timeline hypothesis: a person traveling to the past would exist in the new timeline, but have their own timeline erased.

Thank you to KEVIN BONSOR & ROBERT LAMB for this excellent article.

Here’s some more Paradox theory’s for you to think about ….

As we mentioned before, the concept of traveling into the past becomes a bit murky the second causality rears its head. Cause comes before effect, at least in this universe, which manages to muck up even the best-laid time traveling plans.

For starters, if you traveled back in time 200 years, you'd emerge in a time before you were born. Think about that for a second. In the flow of time, the effect (you) would exist before the cause (your birth).
A math professor travels into the future and steals a groundbreaking math theorem. The professor then gives the theorem to a promising student. Then, that promising student grows up to be the very person from whom the professor stole the theorem to begin with.

Then there's the post-selected model of time travel, which involves distorted probability close to any paradoxical situation [source: Sanders].
What does this mean? Well, put yourself in the shoes of the time-traveling assassin again. This time travel model would make your grandfather virtually death proof. You can pull the trigger, but the laser will malfunction. Perhaps a bird will poop at just the right moment, but some quantum fluctuation will occur to prevent a paradoxical situation from taking place.
But then there's another possibility: The future or past you travel into might just be a parallel universe. Think of it as a separate sandbox: You can build or destroy all the castles you want in it, but it doesn't affect your home sandbox in the slightest. So if the past you travel into exists in a separate timeline, killing your grandfather in cold blood is no big whoop. Of course, this might mean that every time jaunt would land you in a new parallel universe and you might never return to your original sandbox.

Confused yet? Welcome to the world of time travel.

Explore the links below for even more mind-blowing cosmology

A big thank you to Elizabeth Howell November 14, 2017 = Theories, Paradoxes & Possibilities

Time travel may be theoretically possible, but it is beyond our current technological capabilities.

Time travel — moving between different points in time — has been a popular topic for science fiction for decades. Franchises ranging from "Doctor Who" to "Star Trek" to "Back to the Future" have seen humans get in a vehicle of some sort and arrive in the past or future, ready to take on new adventures. Each come with their own time travel theories.

The reality, however, is more muddled. Not all scientists believe that time travel is possible. Some even say that an attempt would be fatal to any human who chooses to undertake it.

Understanding time

What is time? While most people think of time as a constant, physicist Albert Einstein showed that time is an illusion; it is relative — it can vary for different observers depending on your speed through space.

To Einstein, time is the "fourth dimension." Space is described as a three-dimensional arena, which provides a traveler with coordinates — such as length, width and height —showing location. Time provides another coordinate — direction — although conventionally, it only moves forward. (Conversely, a new theory asserts that time is "real.")

Most physicists think time is a subjective illusion, but what if time is real?

Einstein's theory of special relativity says that time slows down or speeds up depending on how fast you move relative to something else. Approaching the speed of light, a person inside a spaceship would age much slower than his twin at home. Also, under Einstein's theory of general relativity, gravity can bend time.

As Marty McFly would say ‘ Doc this sounds Heavy ! ‘

Picture a four-dimensional fabric called space-time. When anything that has mass sits on that piece of fabric, it causes a dimple or a bending of space-time. The bending of space-time causes objects to move on a curved path and that curvature of space is what we know as gravity.

Both the general and special relativity theories have been proven with GPS satellite technology that has very accurate timepieces on board. The effects of gravity, as well as the satellites' increased speed above the Earth relative to observers on the ground, make the unadjusted clocks gain 38 microseconds a day. (Engineers make calibrations to account for the difference.)

In a sense, this effect, called time dilation, means astronauts are time travelers, as they return to Earth very, very slightly younger than their identical twins that remain on the planet.

Through the wormhole

General relativity also provides scenarios that could allow travelers to go back in time, according to NASA. The equations, however, might be difficult to physically achieve.

One possibility could be to go faster than light, which travels at 186,282 miles per second (299,792 kilometers per second) in a vacuum. Einstein's equations, though, show that an object at the speed of light would have both infinite mass and a length of 0. This appears to be physically impossible, although some scientists have extended his equations and said it might be done.

A linked possibility, NASA stated, would be to create "wormholes" between points in space-time. While Einstein's equations provide for them, they would collapse very quickly and would only be suitable for very small particles. Also, scientists haven't actually observed these wormholes yet. Also, the technology needed to create a wormhole is far beyond anything we have today.

Can You Time-Travel?

Alternate time travel theories

While Einstein's theories appear to make time travel difficult, some groups have proposed alternate solutions to jump back and forth in time.

Infinite cylinder

Astronomer Frank Tipler proposed a mechanism (sometimes known as a Tipler Cylinder) where one would take matter that is 10 times the sun's mass, then roll it into very long but very dense cylinder.

After spinning this up a few billion revolutions per minute, a spaceship nearby — following a very precise spiral around this cylinder — could get itself on a "closed, time-like curve", according to the Anderson Institute. There are limitations with this method, however, including the fact that the cylinder needs to be infinitely long for this to work.

An artist's impression of a black hole like the one weighed in this work, sitting in the core of a disk galaxy. The black-hole in NGC4526 weighs 450,000,000 times more than our own Sun. (Image credit: NASA/JPL-Caltech)

Black holes

Another possibility would be to move a ship rapidly around a black hole, or to artificially create that condition with a huge, rotating structure.

"Around and around they'd go, experiencing just half the time of everyone far away from the black hole. The ship and its crew would be traveling through time," physicist Stephen Hawking wrote in the Daily Mail in 2010.

"Imagine they circled the black hole for five of their years. Ten years would pass elsewhere. When they got home, everyone on Earth would have aged five years more than they had."

However, he added, the crew would need to travel around the speed of light for this to work. Physicist Amos Iron at the Technion-Israel Institute of Technology in Haifa, Israel pointed out another limitation if one used a machine: it might fall apart before being able to rotate that quickly.

Cosmic strings

Another theory for potential time travelers involves something called cosmic strings — narrow tubes of energy stretched across the entire length of the ever-expanding universe. These thin regions, left over from the early cosmos, are predicted to contain huge amounts of mass and therefore could warp the space-time around them.

Cosmic strings are either infinite or they’re in loops, with no ends, scientists say. The approach of two such strings parallel to each other would bend space-time so vigorously and in such a particular configuration that might make time travel possible, in theory.

Time machines

It is generally understood that traveling forward or back in time would require a device — a time machine — to take you there. Time machine research often involves bending space-time so far that time lines turn back on themselves to form a loop, technically known as a "closed time-like curve."

The Doctor's time machine is the TARDIS, which stands for ‘Time and Relative Dimensions in Space’.

To accomplish this, time machines often are thought to need an exotic form of matter with so-called "negative energy density." Such exotic matter has bizarre properties, including moving in the opposite direction of normal matter when pushed. Such matter could theoretically exist, but if it did, it might be present only in quantities too small for the construction of a time machine.

However, time-travel research suggests time machines are possible without exotic matter. The work begins with a doughnut-shaped hole enveloped within a sphere of normal matter. Inside this doughnut-shaped vacuum, space-time could get bent upon itself using focused gravitational fields to form a closed time-like curve.

To go back in time, a traveler would race around inside the doughnut, going further back into the past with each lap. This theory has a number of obstacles, however. The gravitational fields required to make such a closed time-like curve would have to be very strong, and manipulating them would have to be very precise. [Related: Warp Speed, Scotty? Star Trek's FTL Drive May Actually Work]

Back to the Grandfather paradox

If that were to happen, some physicists say, you would be not be born in one parallel universe but still born in another. Others say that the photons that make up light prefer self-consistency in timelines, which would interfere with your evil, suicidal plan.

Some scientists disagree with the options mentioned above and say time travel is impossible no matter what your method. The faster-than-light one in particular drew derision from American Museum of Natural History astrophysicist Charles Lu.

That "simply, mathematically, doesn't work," he said in a past interview with sister site LiveScience.

Also, humans may not be able to withstand time travel at all. Traveling nearly the speed of light would only take a centrifuge, but that would be lethal, said Jeff Tollaksen, a professor of physics at Chapman University, in 2012.

Using gravity would also be deadly. To experience time dilation, one could stand on a neutron star, but the forces a person would experience would rip you apart first.

Time travel in fiction

Two 2015 articles by Space.com described different ways in which time travel works in fiction, and the best time-travel machines ever. Some methods used in fiction include:

One-way travel to the future: The traveler leaves home, but the people he or she left behind might age or be dead by the time the traveler returns. Examples: "Interstellar" (2014), "Ikarie XB-1" (1963)

Time travel by moving through higher dimensions: In "Interstellar" (2014), there are "tesseracts" (which is the four-dimensional analogue of the cube) available in which astronauts can travel because the vessel represents time as a dimension of space. A similar concept is expressed in Madeleine L'Engle's "A Wrinkle In Time" (2018, based on the book series that started in 1963), where time is folded by means of a tesseract. The book, however, uses supernatural beings to make the travel possible.

Travelling the space-time vortex: The famous "Doctor Who" (1963-present) TARDIS ("Time And Relative Dimension In Space") uses an extra-dimensional vortex to go through time, while the travelers inside feel time passing normally.

Instantaneous time jumping: Examples include "The Girl Who Leapt Through Time" (2006), the DeLorean from "Back To The Future" (1985), and the Mr. Peabody's WABAC machine from "The Rocky and Bullwinkle Show" (1959-64).

Time travelling while standing still: Both the "Time Machine" (1895 book) and Hermione Granger's Time-Turner from "Harry Potter" keep the traveler still while they move through time.

Slow time travel: In "Primer" (2004), a traveler stays in a box while time traveling. For each minute they want to go back in time, they need to stay in the box for a minute. If they want to go back a day in time, they have to stay there for 24 hours.

Traveling faster than light: In "Superman: The Movie" (1979), Superman flies faster than light to go back in time and rescue Lois Lane before she is killed. The concept was also used in the 1980 novel "Timescape" by Gregory Benford, in which the protagonist sends (hypothetical) faster-than-light tachyon particles back to Earth in 1962 to warn of disaster. In several "Star Trek" episodes and movies, the Enterprise travels through time by going faster than light. In the comic book and TV series "The Flash," the super-speedster uses a cosmic treadmill to travel through time.

Difficult methods to categorize: There's a rocket sled in "Timecop" (1994) that pops in and out of view when it's being used, which has led to much speculation about what's going on. There's also the Time Displacement Equipment in "The Terminator" movie series, which shows off how to fight a war in four dimensions (including time).

So is time travel possible?

While time travel does not appear possible — at least, possible in the sense that the humans would survive it — with the physics that we use today, the field is constantly changing. Advances in quantum theories could perhaps provide some understanding of how to overcome time travel paradoxes.

One possibility, although it would not necessarily lead to time travel, is solving the mystery of how certain particles can communicate instantaneously with each other faster than the speed of light.

In the meantime, however, interested time travelers can at least experience it vicariously through movies, television and books.

Article credits to www.space.com Elizabeth Fernandez

More Time Travel and Philosophy

In general relativity, things called closed time-like curves can exist, and are a way to solve general field equations.

It’s like stepping on a train, taking a wonderful trip through the mountains, and returning to the same spot you left off, both in space and in time.

That means the moment where you step off the train is both in the past and future of when you got on the train in the first place. In a closed time-like curve, an object returns to the same place and time that it was in the past, completing a loop. It’s unclear if closed time-like curves exist in our universe, but if they do, mathematically, they would allow for time travel.

Then there’s option two.

In this quantum mechanical model, each choice opens up another universe. If time travelers changed something in the past, they would enter another parallel universe.

The original timeline would still exist, one among many branching worlds. In such a model, it might be very hard for time travelers to return to the universe they came from.

Finally - if time travel is possible, time travelers can only do certain things.

A time traveler who went back in time, for example, could not kill Hitler, no matter what he tried. This raises all sorts of philosophical problems - does the time traveler still have free will? It’s difficult to say time travel is possible while simultaneously destroying freedom of choice.

Paradox-Free Time Travel While Preserving Freedom of Choice

That’s where young physicist Germain Tobar steps in.

Under the supervision of physicist Dr. Fabio Costa, Tobar came up with a way to mathematically preserve freedom of choice, while allowing for paradox-free time travel.

For example, let’s imagine there is a scientist in a laboratory with a time-traveling coin.

The coin enters the laboratory at some point in the past as “heads” and leaves at some point in the future as “tails”. Tobar’s model fixes the boundary conditions - the point in time where the coin enters and leaves the laboratory - as always heads and tails.

Then, his model allows the state of the coin to change when it is in the laboratory. Since the initial and final state of the coin is fixed, a paradox is avoided. However, anything can happen to the coin when it is in the laboratory. “For example,” says Tobar, “she [the scientist] can decide to always flip the coin, or always prepare heads regardless of what she got... it can flip, it can hit other coins, and so on.” But no matter what she did or how hard she tried, each time the coin time-travels through her lab, it will always leave as “tails”.

Let’s take another pertinent example. “Say you traveled in time, in an attempt to stop COVID-19’s patient zero from being exposed to the virus,” Costa says. “However if you stopped that individual from becoming infected – that would eliminate the motivation for you to go back and stop the pandemic in the first place.”

In Tobar’s model, no matter what you did, the virus would still escape somehow. “You might try and stop patient zero from becoming infected, but in doing so you would catch the virus and become patient zero, or someone else would,” says Tobar. “No matter what you did, the salient events would just recalibrate around you.”

Even time travellers couldn't stop the spread of the coronavirus.

That means that you have complete freedom of choice, but no matter how hard you tried, you could not stop COVID-19 from escaping.

But this is good news for Marty McFly in Back to the Future. Nothing he did could prevent his parents from falling in love and getting married, and eventually, allowing Marty to be born. Other things might change, like how they met, or what his father ate for breakfast that morning. But nothing could change their eventual meeting.

This doesn’t necessarily rule out other models of time travel, for example, a quantum mechanical one.

“Some of the quantum approaches would indeed invoke the existence of multiple universes, which interact through the time machine, possibly creating alternate timelines,” says Tobar. Instead, Tobar and Costa’s model is classical and shows that if only one universe exists, it is possible to allow for paradox-free time travel.

This work has other implications as well, including the unification of quantum theory with general relativity. “One of the main issues is that, in such a theory, time seems to disappear, making the traditional, temporal view of dynamics unsuitable,” says Tobar. “Our work presents a different way to look at physical laws, which could find applications in theories of quantum gravity.”

Could closed time-like curves, and potentially time machines, exist in our Universe?

“Proposals so far involve exotic matter (with negative or infinite energy), and we don't know if such matter exists in our universe,” says Tobar. “An interesting consequence is that the CTCs [closed time-like curves] would only exist after a certain point in time, which means it would not be possible to time travel to before the first time machine was created. This would explain why we haven't seen any time traveler from the future yet.”

And to leave you to ponder on the future in Doc Browns own words :

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