Jaroslav Kores, Ph.D.
What would happen to our body if we flew at the speed of light?

At first, I have to point out that only light can travel at the speed of light — mainly because it has zero weight.
Anything with non-zero weight would require exactly an infinite amount of energy to accelerate to the speed of light, because at the speed of light the weight of such a body would be infinite.
That is certainly not possible.
If anyone is wondering what this behaviour results from, the answer is that the special theory of relativity predicts this behaviour.
Although this may seem strange, it is true and we have a lot of experimental evidence for it.
For example, electrons (tiny light particles) are accelerated almost to the speed of light at CERN and each electron thus increases its weight corresponding to the weight of a high-speed train.
If we modify the question a little bit and wonder what would happen to us if we flew at almost the speed of light, then I must say that nothing special.
Just like when we ride a train or fly an airplane — we don't feel anything special and nothing special happens to our bodies either — this is what Galileo's principle of relativity describes.
That is, if we always move at the same speed.
But we have to somehow reach almost the speed of light.
The human body can handle an acceleration of 1 g (this is the acceleration given to us by the Earth's gravitational field).
To approach a speed of 300,000,000 m/s (roughly the speed of light) we would have to travel at an acceleration of 1 g for almost a year and in that time we would have travelled a distance equal to 28,000 Earth-Sun distances.
In accelerators, this problem is solved by having the shape of a circle and the particles we study make millions of orbits before we let them collide and observe the results of their collision.
More mysteries
Keep exploring questions other readers asked.

Jaroslav Kores, Ph.D.
What would happen if the Earth stopped rotating?
That would probably be pretty unpleasant, I'm afraid it would almost immediately end all life on the Earth. The Earth rotates with a frequency of 1 rotation per 24 hours. By a fairly simple calculation, we can find out t…
Read the answer
Jaroslav Kores, Ph.D.
Is it possible that aliens have visited the Earth in history?
Some materials or products are said not to be "earthly". It's certainly possible, but I'm not aware of any irrefutable evidence for it. Astronomers are convinced that there must be more than 1 planet in the universe to s…
Read the answer
Jaroslav Kores, Ph.D.
Is there a place on the Earth where a person ages faster or slower (very deep underwater or very high in the mountains, etc.)?
I imagine the place where I am on holiday is such a place :D But if we tried to answer this question purely from the physical point of view, there is no place on Earth where we would age noticeably slower ...
Read the answerWant to ask something?
Send us an e-mail with the subject "Physics mysteries" to the address below, or use the contact form.
We can't wait to tackle your interesting questions!