Tapping a message over lightyears in an instant?

  • Thread starter airbourne
  • Start date
In summary: I don't understand the point of the rod idea anyway. Suppose the atoms in the rod DID travel at the speed of light? If you and your friend were 100 light years apart, it would still take 100 of your years to get the message transmitted. We can send messages to each other today at the speed of light, but that doesn't mean that the receipient gets the message instantaneously.Last time I checked you could move a rod that was only a foot long and the other end would respond faster than the speed of sound.Not faster than the speed of sound through that rod. For an iron rod this will be the speed of sound through iron (About 14654mph), for a wooden rod it's
  • #1
airbourne
8
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I have another question (I asked one a month ago, thanks to those who helped clarify it for it). I have not studied physics formally, I am just avidly interested.

Situation:

You have a very rigid rod, 100 light years long. You, and a friend, at the other end of the rod, 100 light years away, know morse code and can easily understand messages by being tapped into your leg. So you set the rod up so it will tap your leg if the other person pushes it forward a little and vice versa.

What prevents the message being delivered in real time (getting the message across 100 light years of space-time in an instant)?

I understand a huge amount of energy would be required to move the rod, let's forget that (unless it is somehow relevant to this hypothetical question) and imagine it's no harder to push than a matchstick.
 
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  • #2
Atoms in the rod push on the next atom, and so on. This disturbance propagates at less than the speed of light. It's called the speed of sound in the medium. It's much less than the speed of light. So your idea of an instantaneous pushing idea doesn't hold up. Relativity still works. Sorry about that. There are no rigid rods; they don't exist.
 
  • #3
airbourne said:
I have another question (I asked one a month ago, thanks to those who helped clarify it for it). I have not studied physics formally, I am just avidly interested.

Situation:

You have a very rigid rod, 100 light years long. You, and a friend, at the other end of the rod, 100 light years away, know morse code and can easily understand messages by being tapped into your leg. So you set the rod up so it will tap your leg if the other person pushes it forward a little and vice versa.

What prevents the message being delivered in real time (getting the message across 100 light years of space-time in an instant)?

I understand a huge amount of energy would be required to move the rod, let's forget that (unless it is somehow relevant to this hypothetical question) and imagine it's no harder to push than a matchstick.
The "tap" will propagate through the rod at the speed of sound of the rod, which is slower than light.
 
  • #5
Thanks, I had wondered if there was a simple law I wasn't thinking of, and thanks ghswllsjr for the link, I can gain a better understanding this this. Sorry for asking something that's been covered, I didn't find anything when I searched.
 
  • #6
I don't understand the point of the rod idea anyway. Suppose the atoms in the rod DID travel at the speed of light? If you and your friend were 100 light years apart, it would still take 100 of your years to get the message transmitted. We can send messages to each other today at the speed of light, but that doesn't mean that the receipient gets the message instantaneously.
 
  • #7
Last time I checked you could move a rod that was only a foot long and the other end would respond faster than the speed of sound.
 
  • #8
John232 said:
Last time I checked you could move a rod that was only a foot long and the other end would respond faster than the speed of sound.

Not faster than the speed of sound through that rod. For an iron rod this will be the speed of sound through iron (About 14654mph), for a wooden rod it's the speed of sound through wood, etc.

Just ot of curiosity; how did you "check"?
 

FAQ: Tapping a message over lightyears in an instant?

1. How is it possible to tap a message over lightyears in an instant?

The concept of tapping a message over lightyears in an instant is based on the principles of quantum entanglement. This phenomenon allows for instantaneous communication between particles regardless of their distance apart. By entangling particles and using them as a communication medium, it is theoretically possible to transmit information over any distance in an instant.

2. Is tapping a message over lightyears in an instant a proven technology?

While the theory behind tapping a message over lightyears in an instant is well-established, the actual technology to achieve this is still in its early stages. Scientists are currently working on developing methods to entangle particles and utilize them for communication purposes, but it is not yet a proven technology.

3. What are the potential uses for tapping a message over lightyears in an instant?

If successfully developed, tapping a message over lightyears in an instant could revolutionize long-distance communication and significantly speed up data transmission. It could also have applications in quantum computing and secure communication, as quantum entanglement is known for its unbreakable encryption.

4. Are there any limitations to tapping a message over lightyears in an instant?

One of the main limitations of tapping a message over lightyears in an instant is the need for entangled particles to act as a communication medium. This means that the technology would only work if there is a pre-established entanglement between the sender and receiver. It also requires precise control and manipulation of particles, which can be challenging to achieve.

5. What are the ethical implications of tapping a message over lightyears in an instant?

Like any new technology, tapping a message over lightyears in an instant raises ethical concerns. This includes potential privacy issues, the possibility of misuse for surveillance or espionage, and the impact on traditional forms of communication. It is important for scientists and policymakers to consider these implications and regulate the development and use of this technology.

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