How To Travel at The Speed of Light

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Discussion Overview

The discussion revolves around the concept of traveling at the speed of light, exploring theoretical ideas and alternative propulsion methods. Participants examine the implications of mass on speed and consider hypothetical scenarios involving gravitational forces, particularly in relation to black holes.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant suggests that instead of pushing a spacecraft to the speed of light, a device could pull it, likening it to a slingshot mechanism.
  • Another participant asserts that the impossibility of traveling at the speed of light is due to the presence of mass, stating that only massless particles can achieve this speed.
  • A different reply challenges the slingshot idea by noting that it would still require 'infinite' energy, thus questioning its feasibility.
  • One participant explains that regardless of speed, the speed of light remains constant at c from any frame of reference, indicating that one can never approach the speed of light.
  • A later contribution discusses the possibility of free falling into a black hole, suggesting that one could reach a relative velocity of c at the event horizon, although this may differ under general relativity.
  • The same participant elaborates on the idea of using a black hole's gravitational pull as a means to achieve high velocities, contrasting it with traditional propulsion methods.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility of traveling at the speed of light, with some supporting the idea of gravitational assistance while others emphasize the limitations imposed by mass. No consensus is reached regarding the proposed methods.

Contextual Notes

Participants acknowledge the complexities of general relativity and classical physics in relation to speed and gravitational effects, but the discussion remains speculative without resolving the underlying assumptions.

JtValentine
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Okay, so I'm no physicist, but I just had a random thought. So they say that traveling at the speed of light is impossible because the mass of the engine would have to be constructed infinitely big. But what if the propulsion didn't come from the spacecraft ?

I was wondering what you guys and gals thought about a device that would pull the spacecraft to the speed of light, instead of push. Think of a slingshot.

It was just a random thought. It may be totally idiotic. I don't know, I just love physics. :)

What do yall think?
 
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The impossibility of traveling at the speed of light results from you having mass. Only massless particles can travel at the speed of light, and they must do so.
 
JtValentine said:
I was wondering what you guys and gals thought about a device that would pull the spacecraft to the speed of light, instead of push. Think of a slingshot.
You'd still need 'infinite' energy, so a slingshot won't help.
 
D H said:
The impossibility of traveling at the speed of light results from you having mass. Only massless particles can travel at the speed of light, and they must do so.

Ah. I'm dumb. Thanks!
 
No matter how fast you are travelling, relative to how you started, you will still measure the speed of light traveling away from you at c. So basically, no matter how fast you get going, you are essentially never any closer to getting to close to the speed of light, since you will always measure the speed of light the same from every frame of reference.

Unless you are a nuetrino of course.
 
JtValentine said:
Okay, so I'm no physicist, but I just had a random thought. So they say that traveling at the speed of light is impossible because the mass of the engine would have to be constructed infinitely big. But what if the propulsion didn't come from the spacecraft ?

I was wondering what you guys and gals thought about a device that would pull the spacecraft to the speed of light, instead of push. Think of a slingshot.

It was just a random thought. It may be totally idiotic. I don't know, I just love physics. :)

What do yall think?

If you have the time to wait, you could let yourself free fall from infinity into a black hole. When you reach the event horizon you should have a relative velocity of c with the black hole in accordance with classical physics. However, GR might determine the relative velocity to be other than exactly c.

If you are in a hurry you could start from a shorter distance from the black hole and accelerate toward it such that upon free falling the rest of the distance to the black hole your relative velocity with the black hole is c when you reach the event horizon. Again, this is according to classical physics.

So in essence a black hole would be pulling rather than pushing you.
 
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