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A few general questions

  1. Apr 4, 2012 #1
    I am 17, studying my first year of A levels. I have been doing a lot of further reading in physics and a few questions have arose in my mind. The likelihood is that they are answerable by correcting my fundamental scientific knowledge as I may have it wrong.

    1. If light cannot escape a black hole due to its infinite gravity, does this mean that light can be effected by other masses with large gravity's such as galaxies etc. If so does this mean that what we see in deep space is actually in an altogether different space?

    2. If the universe is expanding, and the space-time fabric along with it, does this not meant that the fabric of space-time is stretching. If so, this would surely have an effect of mass' ability the 'indent' the fabric, meaning that over the past 14 billion years gravity's effects have altered?

    3. My understanding of the current purpose of the LHC is to find the Higgs-Boson, a particle which theoretically gives mass to particles moving through the Higgs-field. I also understand that as a particle reaches the speed of light its mass rises exponentially. If so, the proton traveling at 99.99% light speed would indeed have a huge mass, which would be a result of it using the Higgs-Boson. If all of this is true then surely we cannot find the particle?

    4. finally, as light leaves distant planets the effects of the expanding universe and gravity cause its frequency to be distorted, giving the impression of colour shift. Does this mean that high frequency gamma rays cannot be seen in the universe as they are constantly being shifted to lower frequency electromagnetic wavelengths?
  2. jcsd
  3. Apr 4, 2012 #2


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    Staff: Mentor

    That is right.
    It can be in a different direction, right.

    I don't understand your question 2. Gravity can work in the same way for 13.7 billion years, with or without expansion of the universe.
    It is one of its targets.
    Usually, the term "mass" means "rest mass", which is the same for all velocities. The energy is increasing, and this is quicker than exponentially.
    No, as the mass stays the same (no you see why mass is defined this way)
    Why? The collisions are energetic enough to produce Higgs particles (as real particles, unlike the field which gives particles their mass).
    constantly being shifted to lower frequency electromagnetic wavelengths?
    They can be seen as gamma rays with lower frequency (or x-rays, depending on the shift). The effect is small for sources nearby, and very large for the early universe. The cosmic microwave background once was visible light, and is now shifted to microwaves.
    Last edited by a moderator: Apr 4, 2012
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