Time travel question

Was bored at work today and this popped into my head for some reason.

Imagine you invented a time machine in your living room. As time is linear and if you went forward or back in time the machine would stay in the same poition where your living room would be at any point in time . It's well known you can't just visit a particular point as the machine doesn't move only time does .

Now imagine if you went forward and there was a nuclear war and a bomb exploded near your house would you die at the point when you passed that time when the bomb went off or would you simply just pass by it and continue to your chosen date??

I'm thinking you'd die as you'd be at that point at which the bomb went off and you'd die the same as everyone else.

Dunno why I thought of that I just did .

according to einstein time travel into the future would only happen if you're traveling at the speed of light. Thus not staying still .
 


I read something interesting about time travel a while ago, had a search and it's discussed in more detail here but the part I found most interesting is:

There's a cosmic speed limit, 186,000 miles per second, also known as the speed of light. Nothing can exceed that speed. It's one of the best established principles in science. Believe it or not, travelling at near the speed of light transports you to the future.

To explain why, let's dream up a science-fiction transportation system. Imagine a track that goes right around Earth, a track for a superfast train. We're going to use this imaginary train to get as close as possible to the speed of light and see how it becomes a time machine. On board are passengers with a one-way ticket to the future. The train begins to accelerate, faster and faster. Soon it's circling the Earth over and over again.

"To approach the speed of light means circling the Earth pretty fast. Seven times a second. But no matter how much power the train has, it can never quite reach the speed of light, since the laws of physics forbid it. Instead, let's say it gets close, just shy of that ultimate speed. Now something extraordinary happens. Time starts flowing slowly on board relative to the rest of the world, just like near the black hole, only more so. Everything on the train is in slow motion.

"This happens to protect the speed limit, and it's not hard to see why. Imagine a child running forwards up the train. Her forward speed is added to the speed of the train, so couldn't she break the speed limit simply by accident? The answer is no. The laws of nature prevent the possibility by slowing down time onboard.

"Now she can't run fast enough to break the limit. Time will always slow down just enough to protect the speed limit. And from that fact comes the possibility of travelling many years into the future.

"Imagine that the train left the station on January 1, 2050. It circles Earth over and over again for 100 years before finally coming to a halt on New Year's Day, 2150. The passengers will have only lived one week because time is slowed down that much inside the train. When they got out they'd find a very different world from the one they'd left. In one week they'd have travelled 100 years into the future. Of course, building a train that could reach such a speed is quite impossible. But we have built something very like the train at the world's largest particle accelerator at CERN in Geneva, Switzerland.
 
according to einstein time travel into the future would only happen if you're traveling at the speed of light. Thus not staying still .
If you create a large enough mass the gravity will distort space-time and you'll experience "time" at a different rate. Earth distorts time enough that the clocks on GPS satellites run a fraction of a second faster than the clocks on Earth. If you could create a huge f***ing mass you could "time-travel" sitting on your arse and literally watch the world go by on Fast Forward.
 
this thread is full of shit like

time travel forward and backwards is only possible as soon as the first time travel machine is invented, hence no one coming back from the future yet.
 
"To approach the speed of light means circling the Earth pretty fast. Seven times a second. But no matter how much power the train has, it can never quite reach the speed of light, since the laws of physics forbid it. Instead, let's say it gets close, just shy of that ultimate speed. Now something extraordinary happens. Time starts flowing slowly on board relative to the rest of the world, just like near the black hole, only more so. Everything on the train is in slow motion.
The faster you go the heavier you get, the heavier you get the slower time goes... basically. It's gravity that slows time.

is only possible as soon as the first time travel machine is invented,
That's just sci-fi mate. It's something Michio Kaku would come out with but it has no basis in science.
 
this thread is full of shit like

time travel forward and backwards is only possible as soon as the first time travel machine is invented, hence no one coming back from the future yet.

You can't travel back in time but can travel forward at a different rate, like marlon says it depends on mass, if you are close to a black hole it's very noticeable.

Another extract from the article I linked to earlier which marlon had touched on as well:

"This is the Global Positioning System, or GPS. A network of satellites is in orbit around Earth. The satellites make satellite navigation possible. But they also reveal that time runs faster in space than it does down on Earth. Inside each spacecraft is a very precise clock. But despite being so accurate, they all gain around a third of a billionth of a second every day. The system has to correct for the drift, otherwise that tiny difference would upset the whole system, causing every GPS device on Earth to go out by about six miles a day. You can just imagine the mayhem that that would cause.

"The problem doesn't lie with the clocks. They run fast because time itself runs faster in space than it does down below. And the reason for this extraordinary effect is the mass of the Earth. Einstein realised that matter drags on time and slows it down like the slow part of a river. The heavier the object, the more it drags on time. And this startling reality is what opens the door to the possibility of time travel to the future.
 
so you are telling me you cant travel back in time travel machines?

lol, so many uneducated people talking so much shite about things they have no clue about and things that dont exist anyway
 
Was bored at work today and this popped into my head for some reason.

Imagine you invented a time machine in your living room. As time is linear and if you went forward or back in time the machine would stay in the same poition where your living room would be at any point in time . It's well known you can't just visit a particular point as the machine doesn't move only time does .

Now imagine if you went forward and there was a nuclear war and a bomb exploded near your house would you die at the point when you passed that time when the bomb went off or would you simply just pass by it and continue to your chosen date??

I'm thinking you'd die as you'd be at that point at which the bomb went off and you'd die the same as everyone else.

Dunno why I thought of that I just did .

I’ve always been fascinated by the idea of time travel, and there is a couple ideas/theories that I quite like:

Theory One: you can only travel so long as that particular time machine exists. So you can only go back as far as the moment the time machine was activated, and if at some point in the future it’s breaks down or destroyed, that means you can only go to the point where it goes “off line”.

Theory Two: a human can only travel within his own timeline, meaning from the moment you were born or when your heart started beating inside the womb, until the moment you die. This could mean you may risk a premature death by travelling beyond the moment of your death. This might also cause one of those paradox things - which tend to give me a headache when thinking about it, so I’m keeping away from that!

I also agree with other posters if your time machine is a fixed point, that means you could end up just about anywhere!
 
I'm pretty sure I read an article on how fast the universe is expanding, and in there it stated that the galaxies towards the edge of the universe are accelerating so fast that no light from them will be seen and they will effectively disappear as they pass the speed of light.
Have a google for Hubble deep field video. Fascinating stuff.
 
Time isn't linear. Space-time is curved. Our planet bends time due to its gravity. It's relative to the observer and their mass.

There is no going "backwards", only forwards. Aka, "Time Dilation".

"Time" doesn't actually exist, it's just a measurement of change. We measure atomic-state changes with things like watches and calenders, we don't measure "Time" itself because it doesn't exist. It's a mathematical concept we use to put things in chronological order. A to B, Monday to Tuesday, etc.

As for your question, it depends. You could theoretically dilate time using gravity so you experience time at a faster rate, but whatever happened to the environment would obviously effect you. However, FTL time travel is different. If you travel FTL then you become massless, if you're massless then things (particles) wouldn't affect you (I think). So a nuclear explosion would have no effect on you.

Any nerds feel free to correct me.

I gave your post a "like" for the explanation of relativistic curved spacetime.

I don't think I agree that you necessarily have to be massless to travel FTL though, unless you're discluding warp travel from your FTL bracket. But then if that were the case, how do you propose to travel FTL?

I'm pretty sure I read an article on how fast the universe is expanding, and in there it stated that the galaxies towards the edge of the universe are accelerating so fast that no light from them will be seen and they will effectively disappear as they pass the speed of light.
Have a google for Hubble deep field video. Fascinating stuff.

I'd be interested in reading this, as we had a discussion on here a few months back about pretty much that in the middle of a "physics question" thread that was originally about something else iirc.

Nothing with mass can travel faster than light. Speed is relative. Two objects moving away from each other (such as in your example of expanding universe) at a combined speed that exceeds c will still be able to see each other, but they will each observe their relative speed as being below c due to time dilation at relativistic speeds.

I'm sure that was our conclusion, anyway.
 
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OP is simply wrong. Time is not linear it is constantly contracting and expanding. Watching Sunderland hang onto a lead for the final 10 minutes appears to drag on for hours, whilst if we are chasing a game the same period only lasts for seconds
 
I'm pretty sure I read an article on how fast the universe is expanding, and in there it stated that the galaxies towards the edge of the universe are accelerating so fast that no light from them will be seen and they will effectively disappear as they pass the speed of light.
Have a google for Hubble deep field video. Fascinating stuff.
 
OP is simply wrong. Time is not linear it is constantly contracting and expanding. Watching Sunderland hang onto a lead for the final 10 minutes appears to drag on for hours, whilst if we are chasing a game the same period only lasts for seconds
That's because we have Half Time at the SoL
 
I don't think we could travel into the future, even if we could travel faster than light. Only back through time.

I imagine it like this;

You're looking at a clock face at precisely 12pm. You then travel backwards away from the clock at the speed of light (whilst still facing the clock). The light that would have bounced off the clock at 1 minute past 12 and into your eyes to tell you it's 1 minute past 12 won't be able to reach your eyes. Therefore you will not see its is 1 minute past 12. You will be travelling at the same speed as the light which bounced off the clock at precisely 12pm. So 12pm is the time you will always see until you speed up or slow down.

If you then travel faster than light (whilst still looking at the clock) you will then overtake and see the light that bounced off the clock at previous times to 12pm, therefore you have travelled back in time.

Obviously it's a f***ing big clock.
 
I don't think I agree that you necessarily have to be massless to travel FTL though, unless you're discluding warp travel from your FTL bracket. But then if that were the case, how do you propose to travel FTL?
Once you go FTL you cease to interact with the Higgs Field, which gives objects their mass, which means you'll be massless. It's why a photon has no mass. Whether anything can actually get up to that speed is debatable. (I say not)

As for "warp" travel, I'm not even sure that's possible mate. I've seen some people say you'd need a particle accelerator as big as our Solar System just to create enough energy to create a warp or "wormhole". Then they do that daft thing when they fold a piece of paper and punch a pen through it... voila! etc, it's just sci-fi imo. How the fuck would you even program a computer to choose a date or location? [10 GOTO 1985, 20 GOTO 10, RUN!] And how would you survive going through it? It's not something they teach you in Physics class, and it's not a question that serious scientists have put any thought into. Time dilation is the only tried and tested means of "time travel", and it only ever goes one way.. "forward".
 
Once you go FTL you cease to interact with the Higgs Field, which gives objects their mass, which means you'll be massless. It's why a photon has no mass. Whether anything can actually get up to that speed is debatable. (I say not)

As for "warp" travel, I'm not even sure that's possible mate. I've seen some people say you'd need a particle accelerator as big as our Solar System just to create enough energy to create a warp or "wormhole". Then they do that daft thing when they fold a piece of paper and punch a pen through it... voila! etc, it's just sci-fi imo. How the fuck would you even program a computer to choose a date or location? [10 GOTO 1985, 20 GOTO 10, RUN!] And how would you survive going through it? It's not something they teach you in Physics class, and it's not a question that serious scientists have put any thought into. Time dilation is the only tried and tested means of "time travel", and it only ever goes one way.. "forward".

Alcubierre drive - Wikipedia
 
The words "speculative" and "negative mass" should slap you in the face like a salmon's arse. It's all mathematical jiggery-pokery.

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α is the lapse function that gives the interval of proper time between nearby hypersurfaces,
βi is the shift vector that relates the spatial coordinate systems on different hypersurfaces,
γij is a positive-definite metric on each of the hypersurfaces.

Hurray we haz time travul! :lol: Try building the kernt I dare ya.

I can mathematically prove that 0.999999.. is equal to 1. It doesn't make it true.
 

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