Why Do You Travel Into The Future As You Approach The Speed Of Light?

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Discussion Overview

The discussion revolves around the concept of time dilation as it relates to traveling at high speeds, particularly as one approaches the speed of light. Participants explore the implications of time appearing to pass differently for observers in various frames of reference, and the paradoxes that arise from these observations.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants assert that time appears to pass more slowly for faster-moving bodies, suggesting that as one approaches the speed of light, time slows down for the traveler.
  • Others argue that while time slows for the traveler, it appears to speed up for observers moving slower than the traveler, creating a complex interplay of time perception.
  • A participant questions the logic of time speeding up as one approaches the speed of light, suggesting it contradicts the principle of time slowing down with increased speed.
  • Another participant emphasizes that one does not need to approach the speed of light to experience time travel into the future, as this occurs at all times, albeit at different rates.
  • Some contributions highlight the misconception of "negative speed," clarifying that while speed is non-negative, velocity can be negative, and this distinction is important in the context of time travel discussions.
  • Several participants reference the twin paradox and the reciprocal nature of time dilation, indicating that both observers perceive the other's time as moving slower.
  • There are suggestions for creating an FAQ to address common misconceptions about time dilation and its implications.

Areas of Agreement / Disagreement

Participants express differing views on the nature of time dilation and its implications for traveling into the future. There is no consensus on the interpretation of time behavior at relativistic speeds, and multiple competing perspectives remain throughout the discussion.

Contextual Notes

Some participants note the limitations of understanding time dilation without a solid grasp of relativity, and there are references to the mathematical aspects of velocity and time dilation that remain unresolved in the discussion.

Who May Find This Useful

This discussion may be of interest to those exploring concepts in relativity, time dilation, and the philosophical implications of time travel within the framework of physics.

Silverbackman
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Time appears to pass more slowly for faster-moving bodies. In other words the faster you travel, the slower time will move for you.

When you reach the speed of light time stops. If you travel faster than the speed of light it is assumed you can go back in time.

All these natural explanations of time seems harmonically sound...until you get to how you can go into the future.

Why does time speed up as a approach the speed of light? Doesn't the violate the "Time appears to pass more slowly for faster-moving bodies" principle. Time going slower as you go faster seems to logically make more sense. Time all of a sudden speeding up instead of slowing down as you approach the speed of light (as will as some other aspects of time dilation) do not logically make much sense.

Instead, it would be more logical to go forward in time with negative speed (t). However we all know that you cannot go at a negative speed, and in this alternative way you cannot go forward in time. This alternative law of nature is similar to the fact that you can't go over the speed of light and therefore you cannot go back in time.
 
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Silverbackman said:
Why does time speed up as a approach the speed of light? Doesn't the violate the "Time appears to pass more slowly for faster-moving bodies" principle. Time going slower as you go faster seems to logically make more sense. Time all of a sudden speeding up instead of slowing down as you approach the speed of light (as will as some other aspects of time dilation) do not logically make much sense.
You misinterpeted that: 1) Time doesn't move faster for you when you speed up time goes slower but for everything that's moving slower then you are time goes faster.
 
What he said.
 
Silverbackman said:
Time appears to pass more slowly for faster-moving bodies. In other words the faster you travel, the slower time will move for you.

When you reach the speed of light time stops. If you travel faster than the speed of light it is assumed you can go back in time.

This is a good opportunity to seek volunteers to write an FAQ for our forum that tackles this misconception about time dilation. Any volunteers?

:)

Zz.
 
You don't need to "approach the speed of light" to travel into the future! You are doing it right now sitting at your desk. As others have pointed out, time slows for an observer moving at high speed relative to others, not speeds up.

I'm not sure what you could mean by " However we all know that you cannot go at a negative speed". "Speed" is by definition (in the strict physical sense) non-negative but you certainly can have a negative velocity.
 
ZapperZ said:
This is a good opportunity to seek volunteers to write an FAQ for our forum that tackles this misconception about time dilation. Any volunteers?

:)

Zz.

I volunteer to write a piece that debunks the "reciprocal time dilation" (aka Dingle's folly).
 
HallsofIvy said:
You don't need to "approach the speed of light" to travel into the future! You are doing it right now sitting at your desk. As others have pointed out, time slows for an observer moving at high speed relative to others, not speeds up.

I'm not sure what you could mean by " However we all know that you cannot go at a negative speed". "Speed" is by definition (in the strict physical sense) non-negative but you certainly can have a negative velocity.

By traveling into the future I don't mean traveling at normal speed. If you go closer to the speed of light you go very quickly into the future if you are the one going close to the speed of light. This however contradicts the fact that time passes slower as you go faster? Should time go even slower if you approach the speed of light? If so why would you nearly "warp" to the future as you approach the speed of light?

By negative speed I mean...say...-10 KPH. It isn't possible, but it would make more sense to travel quickly into the future by going at negative speeds than approaching the speed of light.
 
I think it goes like this. since you are going slower in time. but that's in your reference frame.therefore , for other observers. Time will be normal. So you will have aged less because time for you is slower but time for other people is the same.

So it'd be... say for example 3 years for you but for example it's been 5 years to people on earth. which indirectly means you have gone to the future.

Hope I got it right there.
 
Let me make a few suggestions:

1) take a look at

http://www.onestick.com/relativity/"

to get a better idea on what time dilation due to velocity actually means. The main point you appear to be missing is that if A moves relative to B, A thinks that B's clocks run slow, while B also thinks that A's clocks run slow.

Your next question will undoubtedly be about the twin paradox, but I suppose that can't be helped.

2) Forget about traveling "at the speed of light" or "faster than the speed of light". This is not possible within the bounds of relativity. Asking questions about impossible conditions is an almost-surefire way to confuse yourself.

Do yourself a favor, and attempt to actually understand relativity, and avoid questions about traveling "at lightspeed" and "faster than light" until you do understand relativity.

In this vein, realize that if you accelerate at a constant rate (say 1 Earth gravity) your velocity will always increase, but you will never, ever, no matter how long you accelerate, reach the velocity of light.

BTW, the mathematical formula for your velocity after accelerating by your wristwatch for a time T is

v = c*tanh(AT/c)

Then tanh function approaches 1 as its argument reaches infinity, but never reaches 1

i.e.

tanh(1) = .762
tanh(2) = .964
tanh(5) = .99991
tanh(10) = .999999995

etc.
 
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  • #10
Strategiest said:
I think it goes like this. since you are going slower in time. but that's in your reference frame.therefore , for other observers. Time will be normal. So you will have aged less because time for you is slower but time for other people is the same.

So it'd be... say for example 3 years for you but for example it's been 5 years to people on earth. which indirectly means you have gone to the future.

Hope I got it right there.

Nope. Your time always flows normally, whoever you are, as long as you are inertial (not accelerated). Your instruments show you other people's time flows slower than that. Other people measure your time as slower than theirs, too. All of this time comparison is relative, and the transformations are symmetric; what you see happening to their lengths and times is just what they see happening to yours.
 
  • #11
HallsofIvy said:
You don't need to "approach the speed of light" to travel into the future! You are doing it right now sitting at your desk.

from the '70s there's a pop song by the Steve Miller Band that goes: "Time keeps on slippin', slippin', slippin' into the future..."

i guess we're all time traveling into the future at a rate of 1 minute per minute.

As others have pointed out, time slows for an observer moving at high speed relative to others, not speeds up.

now, if you can spend the entire gross domestic product of the U.S. for a few years, maybe you can build yourself a really fast spaceship with all of the life support systems you need to live for a few years and take about 8 years to fly to Alpha Centauri and back at 0.999 c. it'll seem like about 8 years to you, but when you get back, it will be about 179 years later here. so that would be time-traveling into the future at a rate of 22 minutes per minute.

rots o' ruck.
 
  • #12
rbj said:
now, if you can spend the entire gross domestic product of the U.S. for a few years, maybe you can build yourself a really fast spaceship with all of the life support systems you need to live for a few years and take about 8 years to fly to Alpha Centauri and back at 0.999 c. it'll seem like about 8 years to you, but when you get back, it will be about 179 years later here. so that would be time-traveling into the future at a rate of 22 minutes per minute.
Er, You've got that a little wrong. It would take a little over 8 years Earth time, and about 4 1/3 months for you.
 
  • #13
for the question of traveling into future, i think it is convinience to refer to the twink paradox.
 
  • #14
"Twink" paradox? They have to be THAT young?

:)

Zz.
 
  • #15
what mean by THAT young?
 

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