# Does Traveling at Light Speed Affect Fuel Consumption and Time Dilation?

• daz59
In summary, according to the special theory of relativity, a person in a ship traveling close to the speed of light will only experience one hour passing while the rest of the Earth ages by 100 years. This suggests that the ship would only use one hour's worth of fuel, but in reality, reaching those speeds would require an immense amount of energy and would likely result in the destruction of the ship and its passengers. As the journey becomes more realistic, the amount of fuel needed increases exponentially.
daz59
Something I was wondering, since time slows down as we approach the speed of light. Say a person in a ship travailing close to the speed of light only ages by one hour when the rest of the Earth ages by 100 years, does that mean the ship only uses one hours worth of fuel? But travels 100 years relative to earth?

Darren

daz59 said:
Say a person in a ship travailing close to the speed of light only ages by one hour when the rest of the Earth ages by 100 years, does that mean the ship only uses one hours worth of fuel? But travels 100 years relative to earth?

Darren
if it's not accelerating it won't use any fuel

According to special theory of relativity, when speed limits to speed of light, energy (kinetic energy) limits to infinity. because mass limits to infinity.

m2 = m1 / SQRT(1 - (v/c)^2)

*when we approach the speed of light, necessary amount of energy is too much !

daz59 said:
Something I was wondering, since time slows down as we approach the speed of light. Say a person in a ship travailing close to the speed of light only ages by one hour when the rest of the Earth ages by 100 years, does that mean the ship only uses one hours worth of fuel? But travels 100 years relative to earth?

Darren
The short answer to your question is yes. It is true that the ship, along with everything and everyone in it, will experience a mere one hour passing.

You can also see a mind-boggling implication of this: that star that was 100+ light years away when you were on Earth, is now much, MUCH closer (this is the length contraction component to relativity), which is why it can be reached with a mere hour of fuel expended.

But

As others are pointing out, it's not that easy. Reaching speeds that manifest that amount of time dilation would burn through an unimaginable amount of fuel - even if it could be done - which it can't. The journey specified requires starting out at Earth and achieviing infinite acceleration to .99999+ c (such that there is no ramp up component to your speed) and then reversing at the other end so that you spend your entire 100ly-in-1h journey at .99999+c. Your passengers and equipment will be vapourized.

As you make your experiment more realistic, you will see that the journey must become a long rampup to ~c and then a long ramp down to 0. The time dilation is still significant, but the fuel expended becomes nigh-unimaginably large.

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## What is the speed of light?

The speed of light is approximately 299,792,458 meters per second in a vacuum. This is denoted by the symbol "c" in physics equations.

## Can anything travel faster than the speed of light?

According to Einstein's theory of relativity, nothing can travel faster than the speed of light. This is because as an object's speed approaches the speed of light, its mass and energy increase infinitely, making it impossible for it to reach or exceed the speed of light.

## Does light experience time?

No, according to the theory of relativity, time experiences dilation as an object's speed approaches the speed of light. This means that from the perspective of a photon of light, time does not pass. However, from an observer's perspective, light still travels at the speed of light and experiences time.

## How does light speed affect time?

As an object's speed approaches the speed of light, time experiences dilation. This means that time appears to slow down for the object in motion relative to an observer who is stationary. This effect becomes more significant as the object's speed approaches the speed of light.

## What is the relationship between light speed and the fabric of space-time?

Einstein's theory of relativity states that the fabric of space-time is affected by gravity and the speed of light. The constant speed of light plays a crucial role in determining the geometry of space-time and how it is affected by massive objects.

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