Thread: How short of a wavelength is possible?

1. For electromagnetic waves gamma radiation seems to be the shortest wavelength, but is there some sort of limit on how short of a wavelength they can have?

2.

3. Originally Posted by dan hunter
For electromagnetic waves gamma radiation seems to be the shortest wavelength, but is there some sort of limit on how short of a wavelength they can have?
Ever heard of Planck length?

4. Originally Posted by Howard Roark
Originally Posted by dan hunter
For electromagnetic waves gamma radiation seems to be the shortest wavelength, but is there some sort of limit on how short of a wavelength they can have?
Ever heard of Planck length?

Thats no limit. So far what we know there is no limit.

5. Originally Posted by Gere
Originally Posted by Howard Roark
Originally Posted by dan hunter
For electromagnetic waves gamma radiation seems to be the shortest wavelength, but is there some sort of limit on how short of a wavelength they can have?
Ever heard of Planck length?

Thats no limit. So far what we know there is no limit.
Interesting. How would you measure it, since the lowest measurable length is the Planck length?

6. Where did u read it?

7. Originally Posted by Gere
Here

8. "There is currently no proven physical significance of the Planck length" first sentence.

9. Originally Posted by Gere
"There is currently no proven physical significance of the Planck length" first sentence.
When was proof introduced to science? I guess I missed the email.

10. Originally Posted by Gere
"There is currently no proven physical significance of the Planck length" first sentence.
but you quoted the sentence incompletely, you left out : ".....it is, however, a topic of theoretical research. "
Also, the sentence following the first one is relevant:

"Since the Planck length is so many orders of magnitude smaller than any current instrument could possibly measure, there is no way of examining it directly."

11. Originally Posted by Howard Roark
Originally Posted by Gere
"There is currently no proven physical significance of the Planck length" first sentence.
but you quoted the sentence incompletely, you left out : ".....it is, however, a topic of theoretical research. "
Also, the sentence following the first one is relevant:

"Since the Planck length is so many orders of magnitude smaller than any current instrument could possibly measure, there is no way of examining it directly."
The way way I read the article, there is a theory that the Planck length may denote the smallest measurable length, but this is not taken as universally accepted.

12. Originally Posted by exchemist
Originally Posted by Howard Roark
Originally Posted by Gere
"There is currently no proven physical significance of the Planck length" first sentence.
but you quoted the sentence incompletely, you left out : ".....it is, however, a topic of theoretical research. "
Also, the sentence following the first one is relevant:

"Since the Planck length is so many orders of magnitude smaller than any current instrument could possibly measure, there is no way of examining it directly."
The way way I read the article, there is a theory that the Planck length may denote the smallest measurable length, but this is not taken as universally accepted.
Sure but this sets the marker for what could be the smallest measurable wavelength. That was my point.

13. Originally Posted by Howard Roark
Originally Posted by exchemist
Originally Posted by Howard Roark
Originally Posted by Gere
"There is currently no proven physical significance of the Planck length" first sentence.
but you quoted the sentence incompletely, you left out : ".....it is, however, a topic of theoretical research. "
Also, the sentence following the first one is relevant:

"Since the Planck length is so many orders of magnitude smaller than any current instrument could possibly measure, there is no way of examining it directly."
The way way I read the article, there is a theory that the Planck length may denote the smallest measurable length, but this is not taken as universally accepted.
Sure but this sets the marker for what could be the smallest measurable wavelength. That was my point.
Understood, but if one does not accept it, then there is no limit to the frequency of EM radiation.

14. Originally Posted by exchemist
Originally Posted by Howard Roark
Originally Posted by exchemist
Originally Posted by Howard Roark
Originally Posted by Gere
"There is currently no proven physical significance of the Planck length" first sentence.
but you quoted the sentence incompletely, you left out : ".....it is, however, a topic of theoretical research. "
Also, the sentence following the first one is relevant:

"Since the Planck length is so many orders of magnitude smaller than any current instrument could possibly measure, there is no way of examining it directly."
The way way I read the article, there is a theory that the Planck length may denote the smallest measurable length, but this is not taken as universally accepted.
Sure but this sets the marker for what could be the smallest measurable wavelength. That was my point.
Understood, but if one does not accept it, then there is no limit to the frequency of EM radiation.
agreed

15. Originally Posted by John Galt
Originally Posted by Gere
"There is currently no proven physical significance of the Planck length" first sentence.
When was proof introduced to science? I guess I missed the email.
It's always been there. It's the laws of physics that can't be proven. However when one starts with propositions which are taken as axioms and one uses logic to arrive at a result then the result is called a theorem and it's said that this process "proves" that the theorem is correct. The same thing is done in math too.

Regardless of what the wavelength is, one can always transform to a new frame of reference in which the wavelength is theoretically shorter. Perhaps it can be measured somehow using its energy.

16. Originally Posted by physicist

Regardless of what the wavelength is, one can always transform to a new frame of reference in which the wavelength is theoretically shorter. Perhaps it can be measured somehow using its energy.
This makes no sense since the wavelength is very short, the frequency (hence the energy) is very high, so there should be no need for any transformation into another frame.

17. Originally Posted by dan hunter
For electromagnetic waves gamma radiation seems to be the shortest wavelength, but is there some sort of limit on how short of a wavelength they can have?
There has to be a lower bound. If there wasn't, then the wave energy would be infinite and that is , well, unphysical.
At the other end of the spectrum, you can have as large of a wavelength as you want, the only thing is that , as , its energy goes to zero.

18. Originally Posted by Howard Roark
Originally Posted by physicist

Regardless of what the wavelength is, one can always transform to a new frame of reference in which the wavelength is theoretically shorter. Perhaps it can be measured somehow using its energy.
This makes no sense since the wavelength is very short, the frequency (hence the energy) is very high, so there should be no need for any transformation into another frame.
He asked how short wave length can be. If someone claimed it was L then one can change to another frame in which its less than L disproving that L wasn't the shortest length. What about that are you having trouble understanding?

19. Originally Posted by physicist
Originally Posted by Howard Roark
Originally Posted by physicist

Regardless of what the wavelength is, one can always transform to a new frame of reference in which the wavelength is theoretically shorter. Perhaps it can be measured somehow using its energy.
This makes no sense since the wavelength is very short, the frequency (hence the energy) is very high, so there should be no need for any transformation into another frame.
He asked how short wave length can be. If someone claimed it was L then one can change to another frame in which its less than L disproving that L wasn't the shortest length. What about that are you having trouble understanding?
I have no trouble, I simply pointed out that your changing frames makes no sense. The measurement is done in the frame of the transmotter, in a frame moving wrt. the transmitter you can get any wavelength, so it makes no sense switching frames. This is why your "disproof" is invalid.

20. Originally Posted by Howard Roark
I have no trouble, I simply pointed out that your changing frames makes no sense.
On the contrary. It makes perfect sense. Otherwise I wouldn't have posted it.

Originally Posted by Howard Roark
The measurement is done in the frame of the transmotter, in a frame moving wrt. the transmitter you can get any wavelength, so it makes no sense switching frames. This is why your "disproof" is invalid.
That's wrong. The OP asked For electromagnetic waves gamma radiation seems to be the shortest wavelength, but is there some sort of limit on how short of a wavelength they can have? He didn't mention anything about a source. And if someone wants photons with a wavelength shorter than the one he can produce with a source of photons which at rest in his frame of reference then all he has to do is either change to a new frame of reference in which the source is firing photons in the direction of motion or place his source in motion in the direction in which the source is firing. Either method is possible but I only needed one to disprove that once you find the shortest wavelength then there is none that can be measured which are shorter.

That's why you're wrong.

21. Originally Posted by physicist
That's wrong. The OP asked For electromagnetic waves gamma radiation seems to be the shortest wavelength, but is there some sort of limit on how short of a wavelength they can have? He didn't mention anything about a source.
Of course he didn't, this is not a Doppler measurement, "physicist".

once you find the shortest wavelength then there is none that can be measured which are shorter.
...meaning that you are getting more and more unphysical in your reasoning, as , the wave energy goes to infinity.....

22. Physicist is right, Roark is wrong.

Originally Posted by Howard Roark
...meaning that you are getting more and more unphysical in your reasoning, as , the wave energy goes to infinity.....
So?

23. Originally Posted by Gere
Physicist is right, Roark is wrong.

Originally Posted by Howard Roark
...meaning that you are getting more and more unphysical in your reasoning, as , the wave energy goes to infinity.....
So?
So, this is unphysical, there is nothing in nature having infinite energy.

24. Originally Posted by Gere
Physicist is right
I agree.

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