What would you see if you travel at the speed of light?

[marlon]

Guys,

I think this site might help our purposes too.

Smurf, the answer to your question is in there...Just give up your date and do some physics research man...:)

marlon

 

[ZapperZ]

What would you see if you travel at the speed of light?

Yup. I suppose that would be another question that is too often asked. I'll include that in the list:

1. Since E = mc^2, and photons have energy, doesn't this mean that photons have mass?

2. Why doesn't an electron crash into the nucleus (or something to that effect)?

3. What do I see when I travel at the speed of light?

4. What is energy?

5. What is a photon?

6. Is light a wave or a particle?

Again, if people can pick one of these and volunteer to write a response to such an article, please PM me. I'll try to organize them and, hopefully, after the New Year, we'll have a set of brand-new FAQ's for the physics forum.

:)

Zz.

 

[DaveC426913]

You would see the entire universe die of age in an instant (because time would have stopped for you relative to the rest of the universe). That is, inasmuch as you could see at all - considering all the light you received would be infinitely blue-shifted.

Another way of looking at it is, what if you were a photon? Well, photons do not experience time at all. The entire universe happens to them all at once.

 

[vanesch]

Well, there is of course already the usenet physics FAQ,
http://math.ucr.edu/home/baez/physics/

Maybe we shouldn't re-invent the wheel for the topics that are well-treated there ?

 

[KingNothing]

Actually this has brought up an idea I've had for some time. We all know what FAQs are - frequently asked questions...but howabout IFAQS, or Infrequently asked questions?

It would just be a huge, huge list of all the simple questions we've gotten - you know, about the speed of light, what is a photon, is the HUP real, etc.

On the other hand, although there is some redundancy, if nobody ever repeated a question, there'd be a lot less activity on the board in general.

 

[ZapperZ]

Well, there is of course already the usenet physics FAQ,
http://math.ucr.edu/home/baez/physics/
Maybe we shouldn't re-invent the wheel for the topics that are well-treated there ?

I actually do want to reinvent the wheel, but tailored-made for PF. :)

There's a chance that if we have an FAQ here, that some people might actually read that first before posting their questions. But I will admit that I am not holding out on that possibility too much. There's a notice for them to not post their homework or schoolwork type questions in the General and Classical Physics forums, and people still post their homework questions right underneath the thread that tell them not to do that.

Oy vey.

Zz.

 

[KingNothing]

You would see the entire universe die of age in an instant (because time would have stopped for you relative to the rest of the universe). That is, inasmuch as you could see at all - considering all the light you received would be infinitely blue-shifted.
Another way of looking at it is, what if you were a photon? Well, photons do not experience time at all. The entire universe happens to them all at once.

Wouldn't it be so blue-shifted that it's completely out of our visual spectrum?

 

[vanesch]

Wouldn't it be so blue-shifted that it's completely out of our visual spectrum?

You'd actually be fried like a sausage...

 

[Anttech]

4. Evolution is just a "theory".

Excuse my ignorance (and as a matter of fact I believe evolution to be correct) what is Darwinism if it is not a "theory"?

 

[ZapperZ]

Excuse my ignorance (and as a matter of fact I believe evolution to be correct) what is Darwinism if it is not a "theory"?

I really did not wish that this thread goes into the actual discussion of the questions in the list. It is supposed to be producing such a list and now it is the discussion of getting people to write responses to such questions.

But since you asked, and rather than tell you to go look at my Journal Entry #12, I'll repost what I wrote there:

1. Evolution is only a THEORY.

This stems from the pedestrian usage of the word "theory", meaning to nothing more than an educated guess, if that. It implies that a scientific "theory" is nothing better, not verified, or still not accepted. Again, nothing more than an educated guess.

This argument reveals the ignorance of how the word "theory" is used in science, and especially in physics. There are two broad dichotomy of the nature of scientific studies - experimental and theoretical. Experimental involves experiment! This includes data collection, analysis, phenomenological models, etc. Theoretical, on the other hand, involves either phenomenalogical models of experiments (same as experimental), or theoretical extension of preexisting ideas via ab initio derivation. So a theory is a mathematical/logical description of an idea.

Furthermore, saying something is just a theory somehow implies that a theory can "graduate" into a law or a principle. This of course is absurd. Laws, theories, principles, etc., are all the same. Each may have varying degree of certainty or varification, but it doesn't mean one is better than the other, or that they evolve into one another.

To attack Evolution by saying it is "just a theory" is also an attack on BCS Theory of Superconductivity, Quantum Field Theory, Band Theory of Solids, etc, etc. If one is aware of how successful those physics theories are, one would never make such an idiotic argument. So this is an example of an argument made based on ignorance.

If you wish to discuss this further, I'd suggest we go to the Bio forum that already has a similar thread.

Zz.

 

[Anttech]

I was just curious, and what you stated is correct. I am not saying that it is an educated guess, but a hypothesis which has not been disproved, I was taught that science is all about uncertainty, and you should never be as naive (I know you arent) to say that something is for certain!

The definition of "theory" I was using is elequently defined here:

A comprehensive explanation of a given set of data that has been repeatedly confirmed by observation and experimentation and has gained general acceptance within the scientific community but has not yet been decisively proven. See also hypothesis and scientific law.

http://www.google.be/search?q=defin...client=firefox&rls=org.mozilla:en-US:official

 

[ZapperZ]

I was just curious, and what you stated is correct. I am not saying that it is an educated guess, but a hypothesis which has not been disproved, I was taught that science is all about uncertainty, and you should never be as naive (I know you arent) to say that something is for certain!

The definition of "theory" I was using is elequently defined here:



http://www.google.be/search?q=defin...client=firefox&rls=org.mozilla:en-US:official

But what happens when it is "decisively proven"? Does it get renamed to something else other than a theory? That has never happened! So we're stuck with playing the "name" game rather than looking at the content, which is what is more important. To say that the BCS Theory has not been "decisively proven" and that's why it has the "theory" word associated to it is absurd!

Besides, a physical theory cannot be absolutely proven. It can only be shown to be valid.

Please continue with this line of discussion elsewhere.

Zz.

 

[marlon]

Well, there is of course already the usenet physics FAQ,
http://math.ucr.edu/home/baez/physics/
Maybe we shouldn't re-invent the wheel for the topics that are well-treated there ?

You are correct but what let me answer this : many of those (great) texts are very long. I doubt if people that are not trained to much into physics will read them completely or get the point. I am sure this is not the case. Our vision should be that we make these texts shorter with more structure in them. We want short, clear answers...This is very possible.

regards
marlon

 

[Anttech]

Besides, a physical theory cannot be absolutely proven. It can only be shown to be valid.

exactly

Please continue with this line of discussion elsewhere.

Nothing further to add at my end...

 

[Pengwuino]

*comes streaking in naked* E=mc^2 is just a theory! wake up people!

 

[Nucleonics]

*comes streaking in naked* E=mc^2 is just a theory! wake up people!

:: Does a John Ashcroft and puts a robe around Pengwuino ::
:)

 

[Nucleonics]

It's about time...

One of the things I always see is a lot of confused "philosophy-minded" people trying to get a handle on the notion of "time", or whether it resides only inside the consciousness. And when one throws in words like "4th dimension" into the mix, it all leads to confusion. So I think it would help a lot of people if we explained the basis of time in SR and other areas of physics.

Now if only we had the time for all these misconceptions ;)

Nucleonics

P.S. Under Section 32.I.c of the Physics Forums guidelines, bad puns by newbies are tolerated.

 

[KingNothing]

I think one thing that is often not taken into effect in FAQs is that people want very basic, up-front answers. If that intrigues them, they will do more research on their own.

I know I'm not the only person here who's ever seen a five-paragraph answer to a fairly simple question and not read any of it. Fact is, it's intimidating. Perhaps some sort of "heres the short answer, click for the long answer" system would be useful.

 

[matthyaouw]

How about "Where's my avatar?" and "Why isn't my post count going up?" in PF Feedback and announcements.
I'd suggest "Why was my thread locked?" But since those guys don't seem to bother reading rules & guidelines as it is, I'd guess it would be useless...

 

[JasonRox]

"I was studying String Theory, and I got stuck, but I do know lots."

 

[DaveC426913]

Wouldn't it be so blue-shifted that it's completely out of our visual spectrum?

As stated:
"...considering all the light you received would be infinitely blue-shifted..."
So that'd be a yes.

 

[DaveC426913]

I think one thing that is often not taken into effect in FAQs is that people want very basic, up-front answers. If that intrigues them, they will do more research on their own.

I agree. What I think we need are "layman's" answers. No formulae and a minimum of technical terms.

I know I'm not the only person here who's ever seen a five-paragraph answer to a fairly simple question and not read any of it. Fact is, it's intimidating. Perhaps some sort of "heres the short answer, click for the long answer" system would be useful.

The trouble is that these are not "simple" questions. I think most answers would require at least five paragraphs. Much less will merely prompt a "Yah but" response.

 

[DaveC426913]

What would you see if you travel at the speed of light?

You would see the entire universe die of age ...

Oh duh. You weren't actually asking that question - you were submitting it.
Duh.

 

[marlon]

I think most answers would require at least five paragraphs. Much less will merely prompt a "Yah but" response.

Five very small paragraphs...Trust me, the answers will not be too long. This is one of the basic requirements of this FAQ.


Ya'll be baffled...Just hold on, we got some great stuff comin' up...

marlon

 

[ZapperZ]

The FAQ's for the Physics forums are up and running... or at least, it has been started. It lives in the General Physics forum.

Zz.

 

[inha]

The propagation of light in various media also seems to come up frequently. Maybe some of the resident CMP gurus could cover that? Maybe with a brief mention of polaritions since some doubt the abs/re-em.-picture, although with wrong reasons.

 

[ZapperZ]

The propagation of light in various media also seems to come up frequently. Maybe some of the resident CMP gurus could cover that? Maybe with a brief mention of polaritions since some doubt the abs/re-em.-picture, although with wrong reasons.

Would you like to volunteer?

:)

Zz.

 

[marlon]

The propagation of light in various media also seems to come up frequently. Maybe some of the resident CMP gurus could cover that? Maybe with a brief mention of polaritions since some doubt the abs/re-em.-picture, although with wrong reasons.

Great...You can start writing

Make sure you incorporate the discussion on the contradiction how light can "slow down" although photons have constant velocity equal to c. I think the analogy with the car (with constant velocity) and the three stopping lights explains this very well.

Good Luck

regards
marlon

 

[inha]

hah, I knew I should have put more emphasis on the word guru. Maybe I'll try to scrape something up.

 

[marlon]

Inha,

we are eager to read your contribution to the Physics FAQ... :)

we are veeeery eager...

regards
marlon

 

[Danger]

I've noticed in the Astro section an awful lot of questions based upon a misunderstanding of the expansion of the universe.

 

[marlon]

I've noticed in the Astro section an awful lot of questions based upon a misunderstanding of the expansion of the universe.

would you like to volunteer Danger ? :)

marlon

ps : let's tackle the questions mentioned in our list first. Perhaps later we can solve the more advanced cosmology questions. Hey, we might even create a cosmology FAQ in the appropriate subforum. But i do think we will be needing people like SpaceTiger, Pervect, Nereid on board...My knowledge of cosmology is both limited and a bit rusty to say the least

:)

 

[Danger]

I'm not qualified, Marlon, but otherwise I would. I realize that we weren't planning to add any more right now, but I was worried that I might forget to mention it later. That happens a lot.

 

[marlon]

I'm not qualified, Marlon, but otherwise I would. I realize that we weren't planning to add any more right now, but I was worried that I might forget to mention it later. That happens a lot.

Hey Danger, don't be so modest. I have read many of your posts and i liked both the message and the way in which you presented your message. You have a very clear way of writing and that is what we need. So far, i think there are not too many people working on this. So, if you feel like it, i would appreciate the fact that you write an answer to one of these questions. The answers are required to be understandable and , having read your posts, "writing crystal-clearly" is a quality you possess.

In short, please reconsider, please...you can pick any question or add one...:)

regards
marlon

 

[Danger]

Once again, Marlon, I think that you overestimate my abilities, but thank you. Okay, I'll take a shot at the hovercraft one.
As for the expansion thing that I mentioned, it would probably be best to just copy one of Space Tiger's beautifully crafted responses on the subject.
So, where do I submit the thing once I get done?