Recent content by Theoretician

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    Quantum immortality

    You miss the point LnGrrrR. There are no 900 year old people in 'my' universe because the conditions that ensure my survival are extremely unlikely to do so for someone else for such a length of time. So it goes, any person to have ever existed (or, indeed, any person that could have possibly...
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    Quantum immortality

    RVBuckeye I see what you mean but, without any predictions about what should change, it can't really be held up as evidence that the idea is wrong. Sherlock You are very dismissive. I am not necessarily a believer in the MWI but the idea provides a certain symmetry don't you think? I...
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    Quantum immortality

    I'm not certain if, strictly, this should be in the general discussion forum but the idea is based on quantum ideas so I have put it here. If I am mistaken, please, move it. I stumbled upon this idea when I was reading through lots of different interrelated articles on Wikipedia (it can be...
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    Richard Feynman Lectures on Light

    Wonderful. I have revision that I have to do now so I don't know when I'll watch them all but I definitely will.
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    Phase velocity, Group velocity

    Thank you, I shall have a look but I actually think that I have a good enough understanding now having read a few relevant sections in the Feynman Lectures (sorry, this is what I should have done first).
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    Phase velocity, Group velocity

    Would someone be kind enough to please give physical meanings to these two terms? I have never fully understood their meaning and difference (although I know how to express them mathematically). If, say, I have a Gaussian-shaped signal in the frequency domain that I am sending through a...
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    When a free proton captures a free electron

    Or (for completeness) several photons whose sum is the ionization energy.
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    Greatest physicist of all time?

    Exactly, this is why it is very hard to see past Newton as the greatest physicist ever.
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    Twice as hot?

    Surely, it is only technically acceptable to say it if the temperatures are measured on an absolute scale (such as the Kelvin scale)?
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    Basic concept in special relativity

    Nicely put rbj. At first, I thought that it doesn't cover the situation where the light source is stationary and the observer is moving but, from the observers point of view, the source is moving not him and, so, to him, your argument should still apply. If it didn't, the laws of physics would...
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    QED vs Point Charge of the Electron

    Excuse my ignorance but how so?
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    About EM waves

    Whilst that isn't how I understand it, it could be one correct way to understand the situation. My understanding is that virtual photons propogate and cause the electric field and real photons are emitted as EM radiation when charges accelerate. You seem to be saying the inverse of this. An...
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    Basic concept in special relativity

    Thank you for all replies. I will have to work on my communication skills regarding science. I often feel, when I return to special relativity having not considered it for awhile, that I have to partially learn the subject all over again (that, in a sense, being part of the reason that I...
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    Basic concept in special relativity

    I was asked (on another non physics site) how an observer can measure the speed of light to be the same as someone who is moving away/ towards the light source. I know that it is a fairly simple idea but I couldn't find the words to answer comprehensively. Here is what I wrote: In...
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    Okay, clear this up for me

    I believe that dark matter is thought to have exotic properties such as possibly only interacting via the gravitational force (hence, why it has only been 'detected' through it's gravitational influence). If that is the case, I suppose that the dark matter 'on' your table would pass through the...