Time Travel is impossible because

Time travel is impossible
If we were to travel ahead in time because of the constant evolution of bacterias and virusus we would be attacked and killed by bacteria that our bodies couldnt handle
if we traveled back in time we would make every body sick

That’s not WHY it’s impossible. That’s just an issue we would have to take into consideration if it it WERE possible.

Related column.

the black plague was a failed experiment in time travel

You just said time travel was impossible. Now you say someone did in fact go back and give everyone the plague? Which is it?

There is no possible way to go back in time, although you can shrink time the faster you travel.

You cannot go forward in time.

Yes, you can. You’re doing it right now. We all are.

:wink:

Actually, time travel to the past can’t be ruled out but there some non-trivial engineering issues that would have to worked out.

Thing is, even if it’s successfully completed, no one be able to move further back than the time Project Stargate was brought on line. Great for our descendants living in 10000 ACE but no so great for us, and even they won’t be able to visit the grassy knoll in Dallas in November, 1963. Furthermore, that downstream end will forever be moving towards those descendants at the rate of one second per second.

The article goes on to say that physicists have found no evidence of time travel in the universe, and they’ve been looking.

If you have a powerful rocket then you can get relativistic time dilation effects.

Send one twin off on a high speed run out there and back. When the twin comes back he can get a Bad Disease from the other’s twin descendants.

Nothing “impossible” about it from a Scientific point of view.

The Real Question is what happens when you put one end of the wormhole inside the other end? The ouroboros to end all ouroboroses.

I registered to comment on this topic. I believe that we are all looking at this wrong.

First, clearly time travel IS possible. Someone jokingly pointed out that we are traveling forward in time always. That isn’t just a joke, it is a fact that needs to be considered. Second, others have mentioned Einstein’s special theory of general relativity which hypothesizes that the laws of physics are the same for all non-accelerating observers and that the speed of light within a vacuum is the same no matter the speed at which an observer travels.

This allows for a different kind of time travel. It allows for us to travel forward in time (in theory - assuming we could overcome the difficulties involved) at a much faster rate of speed than “normal.” This has been observed in space travel already.

There are tremendous implications here. Time is clearly not the constant we imagine. It is only a constant to the observer and is highly dependent on the velocity of the observer. An observer not moving at all may not experience time. Perhaps we are all experiencing time at the rate we do based on the speed of our planet revolving around the sun, and the speed of our solar system traveling through space and the speed of our galaxy traveling through the universe, none of which are negligible. What is time like for an observer moving at virtually zero mph?

And the faster we travel, the closer we come to time disappearing into infinity. Sounds a lot like God talk…

Here’s where I think we fail. We make assumptions based on our senses. I like to consider a 2 dimensional man. Imagine the world to him. He simply cannot fathom things that are simple to us. For a two dimensional man, a circle looks like a straight line coming towards him. A straight line that is getting larger and larger. A line might look like a dot sometimes. It might look like a “line” at other times, depending on the angle at which the line is turned towards him. If he was looking at the line perpendicularly it would look like a massive line, or wall. If he was looking at it from 90 degrees off of perpendicular, it would look like a dot.

My point being that we are in a 3d world with five senses and we have also created equipment that can measure other things within our dimensions. You could make an argument (that I would not be comfortable with) that time is the fourth dimension. But I find that hard because time seems very malleable - or at least it is not a constant - except from the observer’s pov.

Time seems to be a construct or an invention. Something created so that we can experience a 3d world in a sensible way.

There is so much interesting discussion to be had on these topics. I am not challenging or arguing with anyone, just trying to learn more and trying to see if there is a way to understand something that is clearly on the outer edge of our ability to comprehend. It may simply not be something we can understand from our limited perspective. Like the 2D man trying to comprehend 3D structures. But it is fun to try.

I’d love to hear from anyone with theories and ideas on this topic.

One thing that does SEEM to be impossible is traveling in time BACKWARDS. It appears that anything that has happened is unchangeable. I can’t prove that, but I also haven’t heard an argument that would allow for it happening and it seems to create paradoxes and other impossible situations.

Time Travel seems to be limited to changing the speed at which we can travel forward, slower or faster.

-Tom Steele

I’ve always like the hypothesis that time travel backward happens all the time. It plays hell with causality of course, and stability in the system is finally achieved when the time machine is eventually prevented by a traveler from being invented.

Oh, and :).

I think you may have blown his mind.

Welcome to the board, hope you find more to stay for!
Gotta say, I was kind of shocked to reach the end and see the signature. Didn’t realize that you were a big nerd. Now I’m waiting for John Boy to weigh in…

Niven’s Law Niven's laws - Wikipedia

“If the universe of discourse permits the possibility of time travel and of changing the past, then no time machine will be invented in that universe.”

Time travel can mean different things, but I’ve always had one major issue with the most common sci-fi version; i.e. a human, as presently constituted (“Back to the Future”-style with all current memories, knowledge, chemical construction, etc.) can take his or her whole self to a specific place in the past. My issue is that we’re each essentially the combination of all the specific atoms and molecules in our bodies. So let’s just say that I want to go back to 100 years ago. The water, carbon, calcium and iron in my body was already “in use” doing something else on earth. If I jump in the Delorean and take myself to the year 1919, would I somehow “borrow” each individual molecule necessary to recreate myself when I get there? The silver filling in my tooth might have been in the necklace of another person at that time. That silver can’t be in two places at once.

There are theories that the water in earth arrived much later than the original forming of earth, most through ice-filled asteroids or comets. What would happen if I set the time machine to earth before the arrival of water? How would I, who is basically a bag of water, possibly be able to exist at that time? That water was still in some asteroid flying around the cosmos. If I went further back, the iron in my blood might not have even been in existence yet. Maybe the supernova that created it hadn’t yet occurred. So where am I getting the iron for my blood when I get there if it hasn’t even been created yet, or is still buried in some aging star?

Time travel is impossible because there’s no such thing as time.

it’s a one-way trip, though; no coming back and wowing the locals with your infinite knowledge of the future.

D’ja ever read Tao Zero? A Bussard ram jet has an accident and can neither slow down nor shut off the jet – they must accelerate until makes billions of years pass in in a subjective moment for the crew.

Whilst there is a “speed limit” to the universe, there isn’t the opposite. You can’t come to a universal full stop.

Just look around you–you are surrounded by things moving at virtually zero MPH–Olympic sprinters, race cars, speeding bullets, jet fighters–all are traveling nearly as slowly as it is possible to travel (just as our environment is very nearly as cold and very nearly as low-gravity as it is possible to get.)

Obviously, if you go back in time, then all of your atoms go back in time, too. It’s not like you need to use the atoms that are “already there”.