Time travel Definition and 350 Threads

Note: For copyright reasons, I'm trimming the original post, which appears to be a direct quote from http://news.yahoo.com/s/livescience/20070820/sc_livescience/timetravelmachineoutlined Also, the peer-reviwed article is at...

Dr. Ron Mallett shares his research into time travel. http://www.coasttocoastam.com/ This is highly controverial, and my understanding is that it has been shown that his solutions are not valid. A PF discussion about this: https://www.physicsforums.com/showthread.php?t=147946

does anyone thinks time travel is possible?

There was some publicity recently about John Cramer not being able to get funding for an experiment that he claims could prove "retrocausation" or backward time travel. I'm confused as to what the experiment is supposed to show. Cramer seems to be saying the outcome will depend on whether or not...

How many of you over here are familiar with the twin paradox? I am personally quite fascinated with this phenomenon predicted by General Relativity. In a nut shell, since your relative time slows down at speeds close to the speed of light, it implies that if, say, your twin brother were to go...

I saw this paper on time travel. Does anyone think its plausible?http://www.physics.uconn.edu/~mallett/main/research_activities.htm

I'm not buying this for reasons of paradoxes, but Brian Greene is saying that time travel backwards is possible. Source what do you guys think?

Anyone have any good reads they want to recommend?

Hi. For a physics project, i was to select a topic that interests me, and give a presentation on it. The topic i chose was: "The possibility of time travel" I started to read more into it, and I am beginning to think that its way out of the scope of my knowledge, as most of the information...

What do you think of this theory, time travel will never be created because if it was, then people in the future would have come back to the past and we would know about it by now. Unless of course a select few were able to go to the past, and told nor interacted with anyone. But my idea was...

Ok...I know there have been tons of threads on this, but I would like to hear some opinions on this. So, after reading and reading about this I have learned that there are tons of theories and reasoning as to why it is possible, but what I really want to know is what all of your opinions are...

does anyone have any equations for calculating time travel without an accelration close, equal or greater than the speed of light or equations or theories that would help me understand traversable wormhole theories and how to calculate them

Ok, I know you all probably get a ton of lame questions about time travel so I thought I'd add another. If I could travel back in time, would I not be adding extra matter & energy into the universe? What I mean is, my old body & my "future" or "present" body would be added into the...

I was reading something about spacetime, and I have a question. Space and time are interwoven with each other and unless my understanding is utterly wrong, as an object's speed increases, time slows down. Thus, time slows with increasing acceleration. As well, the law for all motion under...

We all know by Einstein's Special Theory of Relativty that when an objects at the speed of light, it could move foward in time quicker than the other people. However, I was wondering. Is time travel possible for going back into the past? Can we rewind time as if any two oppposites in nature...

OK, I made another post on this, being too sure of myself that I knew this the answers. This is the wrong thing to do on a forum when everyone else knows more than you :smile: So, I'll try to make it more reasonable this time. Doesn't general relativity allow the *theortical* possibility...

I have a theory, please correct me if I'm wrong. What if the big bang didn't start the universe from expanding? If we were speed up to the rate the universe is accelerating in, where would we be? How did it start? Well I have an answer, I am not sure about the big bang theory being...

do you think it's a good idea to write a 10 page research paper on time travel? if not on time travel, could you possibly suggest something in modern physics that i can easily write a research paper on?

Hi, In Hawking's A Brief History of the Universe, he describes a scenario in which it is possible to travel "back" in time. He says, if faster-than-light time travel is possible, it would then be possible to see a race in one location in space, travel to another part of space to relate the...

Since theory of relativity predit time dilation effects . So does it mean that we can travel backwards or forward in time ?

"Gravity doughnut" may solve time travel problem http://www.nature.com/news/2005/050711/full/050711-4.html

This one just popped into my head while I was on my bed last night. Leave the possibility of time travel backwards, but if it were to become possible in near future , then wouldn't it be possible that as we go back in time , we keep getting younger and probably disappear once we pass the date...

New model "permits time travel" Quoted from http://news.bbc.co.uk/1/hi/sci/tech/4097258.stm Basically, what is said is that a superposed quantum wave is allowed to travel back in time. They make a clear distinction between a collapsed WF and a superposed. Also measurement device is...

Hi folk, In the various literature I have read relating to time travel there always seems to be an assumption that if one traveled in time from a time machine located in say one's own living room one would reappear in the same living room (site thereof) either in the present or the future. Is...

Quantum mechanics has actually shown thru the quantum eraser experiments that we can rewrite the histories of photons, and that time is symmetrical. The best example of this is the translational interaction or pilot wave theory, where a particle future and particle past selves our in constant...

I'm interested in knowing anything about time travel into the past. If anyone has any insight about this it would be helpful.

Time Travel = Infinite Harry Potter's ? This contains a Harry Potter *SPOILER* ...but I'm using it as a background for a question about Time Travel in general. In J.K. Rowling's book, "Prisoner of Azkaban" when Harry is surrounded by dementors, he suddenly sees a stranger who looks...

Time travel can occur in general relativistic models in which one has closed time-like curves (CTC's). A time like curve is simply a space-time trajectory such that the speed of light is never equalled or exceeded along this trajectory. Time-like curves thus represent the possible trajectories...

In his book "the universe in a nutshell", stephen hawkings is discussing the possiblity of time travel to the past (ch. 5 How to protect the past). He introducted the concept of cosmic strings to explain that. would anyone here could explain this concept and it's relation to time travel...

What prompts me to write this is all the conjecture about time travel. Shouldn't we be a bit more down to Earth about all this? All too many of us seem to generate concepts that are not even suggested by the original theories ... especially matters dealing with relativity. Remember all the...

Is it true that space can be curved around and loop itself to a point in the past? If this is true, then time travel to the future and the past should be theoreticly posible. I'm trying to further uderstand relativity, this is why I ask. If we could travel to the past, maybe we can really see...

People say and have decently backed up that time travel is not possible by saying that you would have to rearrange every particle back to where it was. Instead of rearranging the particles of everything. What if u could take all the information and I mean every aspect and formation of every atom...

People say and have decently backed up that time travel is not possible by saying that you would have to rearrange every particle back to where it was. Instead of rearranging the particles of everything. What if u could take all the information and I mean every aspect and formation of every...

I have a unclear problem about time travel: As you all know,when a spaceship move pass Earth with the speed nearly c, the observer will regconise that the watch on the spaceship is moving slower than his own clock. However, to the astronaunt who is on the spaceship, what he saw is the Earth is...

Time Travel. Is it possible?

do you people believe in time travel? I do not mean to be able to slow the time down, but to actually go backwards in time! Please give reason too (if possible

If time travel was ever invented, someone would have come back in time and we would have recognized them. If i ever invent time travel, i will return to this spot right now. *pause* I guess time travel will never be possible. Even if they invented some way of cloaking and forced people to use...

The fantasy of "Time Travel". The discussion of time travel into the past is science fiction at its best. To think there is any way to stop the flow of the universe into the future, then make it flow in reverse just for human amusement, is fantasible. How can one travel back in time to a...

My name is James Reinlie, I live in Central Florida. I'm 15 years old and I am very interested in Einsteins theory of Relativity. But I feel that he has a flaw in his formulas. He states that no object can travel the speed of light besides light energy itself. But, if a object were to travel at...

Time travel?? I was wondering if its actually theoretically possible to travel back in time. I know its possible to "travel to the future" because of time dilation, but I just don't understand what the deal is with traveling back in time. I've heard many times since I was a little boy, that...

I'd been meaning to post about this book a while ago. I read it before school was even out, but since i read it I've just become really interested in physics and astronomy books. So I've been reading too much to post often basically. Anyways, 'Time travel in einstiens universe' by richard...

I tried to find the announcement, but couldn't find it. Why was forum 56 (the Time Travel Forum) removed?

Ok hear is a senario. Let's say time travel is possible. Jack and Jill discovered a way to travel to the future. Jack and jill are both In the same room. jack travels 1 year into the future. Jack would see his basement one year older still made up from the same matter it was made up from a year...

If you time travel in one direction you should finish up were you started. Right back at square one. No need to travel back wards at all. Travel forward in time till you finish up in the past. Thanks for reading my post, Blair Styles. 11:11

Time Travel has been a common staple in the science fiction genre and a topic that I always found interesting. In movies and books I learned that there are three types of time travel: paradoxical, parallel and repetitive. The first type of time travel is known as being paradoxical, where the...

What would be the state of a universe that contains only antimatter? Is it in a state of contraction or expansion similar to ours? As what Feynman diagram shows antiparticles travel backward in time, so if we can transform ordinary matter into antimatter by changing the protons to...

Hi guys, Relativity says (actually, proves) that nothing & absolutely nothing can be faster than light (assuming the body has mass).. Now, its also said that we can reverse or slow down time, if we move with the speed of light or even approach it.. Its a proven fact that time slows down...

The Book with Seven Seals. What type of book was it ? This is an investigation using the methods explained by Ronald Pegg that show ancient texts describe modern objects. Revelations 5:5 "…behold, the Lion of the tribe of Juda, the Root of David, hath prevailed to open the book, and to...

Recently, I went through a sort of "stage" where i wanted to disprove everything worth disproving, and we all know, if you move one card at the bottom of a stack, you change quite a bit. What i did was try to figure out the atomic theory structure. I wanted to see if it was right. I came up with...

If I say die at 45 have have myself frozen and in 500 years time they unthaw me medicine is advanced they can bring me back to life with my memory just as how I knew it before I passed away than from my point of view id have trvelled in time to 500 years into future right ? no diff from a time...