Faster than light: Instantaneous lever

In summary, this weekend-wonderr has not been validated by professional physicists and it is not something that one could use to send information faster than light.
  • #1
ISamson
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Hello.
I have been thinking on faster than light things. I thought about: chemical engines, lasers, wormholes... All that kind of cool, advanced physics.
But, I stumbled on faster than light mechanical actions. I thought about a lever: first class, if you wish, if you apply a force to one side, then something instantaneously occurs on the 'load' side of the lever. This change in speed, direction is instantaneous, which is faster than light, right?
Could this be used in travel?
Please don't judge me on my weekend-wonders.
 
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  • #2
ISamson said:
if you apply a force to one side, then something instantaneously occurs on the 'load' side of the lever.
No, it travels at the speed of sound in the lever.
 
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  • #3
A lever would be solid. Movement propagates through real objects at the speed of sound (only) through an object.
(Beat me to it!)
 
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  • #4
A.T. said:
No, it travels at the speed of sound in the lever.
sophiecentaur said:
Movement propagates through real objects at the speed of sound (only) through an object.
Sound.
I didn't know that! Why? I always thought it would be instantaneous.
 
  • #5
ISamson said:
Sound.
I didn't know that! Why? I always thought it would be instantaneous.
Because both sound and force travels by means of molecule-to-molecule interaction, each interaction taking a tiny bit of time. And there can be a lot of molecules from one end of a lever to another. It is not instantaneous.
 
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  • #6
“Sound” is just a general term for any disturbance. The atoms are displaced as the lever is moved and they push-pull nearby atoms. Any material will deform and that takes time. Hence the finite time to propagate sound or a twist.
 
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  • #7
ISamson said:
Sound.
I didn't know that! Why? I always thought it would be instantaneous.
The speed of sound in a material is defined as the speed at which mechanical changes propagate in that material. It happens at that speed because that is how that speed is defined
 
  • #8
Dale said:
The speed of sound in a material is defined as the speed at which mechanical changes propagate in that material. It happens at that speed because that is how that speed is defined
In a fluid like air, it is easy to define a "speed of sound" because the disturbance that propagates is always a compression wave. The properties of the fluid, specifically its density and its compressibility, allow one to calculate that speed from first principles. Or one can measure it with a starter's pistol, a stopwatch and a wall.

In a solid like steel there are two different types of disturbance that can propagate. You can bang a hammer on the end of a steel rod and see how long it takes before a microphone at the other end picks up the compression wave. Or you can try to swing it like a bat and see how long it is before the resulting "shear wave" reaches the far end so that the end starts to move. The speed of a compression wave depends on the compressibility of the steel -- its bulk modulus. The speed of a shear wave depends on its lateral stiffness -- its shear modulus.
 
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  • #9
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  • #10
jbriggs444 said:
You can bang a hammer on the end of a steel rod and see how long it takes before a microphone at the other end picks up the compression wave.
And this experiment has been done, I think by a member of this forum. And it would also make a good basis for a high school science fair project.
 
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  • #11
ISamson said:
Please don't judge me on my weekend-wonders.

Fair enough, but I think it's also fair to criticize you for the title, where you claim that you have found something that a century of professional physicists did not - merely by "weekend-wondering".

ISamson said:
I didn't know that! Why?

I would think about it from the other direction than most responses. If x is the speed that a mechanical disturbance propagates, what is the relationship between x and something we call "the speed of sound" (which is a kind of mechanical disturbance). i.e. don't get too caught up in the word "sound".
 
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  • #13
"Weekend wondering"? We have to be careful about how we criticize insights. Einstein's insights didn't occur in a research lab after years of painstaking experimentation. The ideas came as insights, flashes of genius, that then took years of painstaking work to flesh out. Human creativity is a nebulous process. Many of the greatest tech companies originated in garages where the founders had some pretty "wild" insights which certainly could have been Weekend Wonderings. Often the level of pure creativity in those austere places equaled or exceeded what was done in the multi-billion dollar research labs. If only creative insight could be legislated by aggressive managers, we'd have a lot of really great insights. Unfortunately, we can't drive when or where the creative insight will come, and the harder we try and drive it, the greater the possibility that nothing will result. What we can do is be aware when those insights come, we have to act on them.
 
  • #14
trainman2001 said:
"Weekend wondering"? We have to be careful about how we criticize insights. Einstein's insights didn't occur in a research lab after years of painstaking experimentation. The ideas came as insights, flashes of genius, that then took years of painstaking work to flesh out. Human creativity is a nebulous process. Many of the greatest tech companies originated in garages where the founders had some pretty "wild" insights which certainly could have been Weekend Wonderings. Often the level of pure creativity in those austere places equaled or exceeded what was done in the multi-billion dollar research labs. If only creative insight could be legislated by aggressive managers, we'd have a lot of really great insights. Unfortunately, we can't drive when or where the creative insight will come, and the harder we try and drive it, the greater the possibility that nothing will result. What we can do is be aware when those insights come, we have to act on them.
Except, the successful examples that you mention of insights and invention have an important difference from the weekend wonderings of some folks based on pop-science and YouTube videos they have watched. If you want to discuss that difference, you should probably start a different thread, since it would be off-topic for this thread. :smile:
 
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  • #15
The question is adequately answered, so I think this is a good place to close the thread.
 
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1. What is the concept of "Faster than light"?

The concept of "Faster than light" refers to any object or particle that can travel faster than the speed of light, which is approximately 299,792,458 meters per second in a vacuum. This concept is often explored in science fiction and has been a topic of scientific research and debate for decades.

2. Is it possible for anything to travel faster than light?

According to our current understanding of physics and the laws of the universe, it is not possible for any object or information to travel faster than the speed of light. This is because, as an object approaches the speed of light, its mass increases exponentially and would require an infinite amount of energy to continue accelerating.

3. What is the "Instantaneous lever" and how does it relate to faster than light travel?

The "Instantaneous lever" is a theoretical device or method that would allow for instantaneous communication or transportation between two points, regardless of the distance between them. It is often used in science fiction as a way to explain faster than light travel, but it has not been proven to be possible in reality based on our current understanding of physics.

4. Are there any experiments or theories that suggest faster than light travel could be possible?

There have been various experiments and theories proposed that suggest the possibility of faster than light travel, such as the Alcubierre drive which uses the concept of warping spacetime. However, these theories are still highly speculative and have not been proven to be feasible or scientifically valid.

5. What are the implications of faster than light travel for our understanding of the universe?

If faster than light travel were to become possible, it would require a major overhaul of our current understanding of physics and the laws of the universe. It could also open up new possibilities for space exploration and potentially allow us to travel to distant galaxies and planets within a reasonable timeframe.

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