Why Does Light Travel?

Discussion in 'Bad Dog Cafe' started by homesick345, Mar 20, 2016.

  1. teletimetx

    teletimetx Doctor of Teleocity

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    ? ... the so called known galaxy? Is there an unknown so called galaxy? Is it that you don't believe in galaxies or the Milky Way? I've not heard much controversy surrounding the concept.

    I think most people refer to the so called known galaxy as the Milky Way. Is there some other theory you are referring to?

    Wiki says this:
    The Milky Way is a barred spiral galaxy that has a diameter usually considered to be about 100,000–120,000 light-years but may be 150,000–180,000 light-years. The Milky Way is estimated to contain 100–400 billion stars although this number may be as high as one trillion. There are likely at least 100 billion planets in the Milky Way. The Solar System is located within the disk, about 27,000 light-years from the Galactic Center, on the inner edge of one of the spiral-shaped concentrations of gas and dust called the Orion Arm. The stars in the inner ≈10,000 light-years form a bulge and one or more bars that radiate from the bulge. The very center is marked by an intense radio source, named Sagittarius A, which is likely to be a supermassive black hole.
     
  2. kwerk

    kwerk Poster Extraordinaire

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    Hmmm. A rather defensive reaction I would have said, to the "so called known" epithet. Let's just extract a couple of bits from the wiki article you've quoted.

    "100,000–120,000 light-years but may be 150,000–180,000 light-years"
    "100–400 billion stars"
    "likely at least 100 billion planets"
    "about 27,000 light-years"
    " likely to be a supermassive black hole"

    None of those say "known". They all say "best estimate". :rolleyes:
     
  3. BigDaddyLH

    BigDaddyLH Telefied Ad Free Member

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    There is creation, upkeep and destruction: Brahma, Vishnu and Shiva.
     
  4. Davecam48

    Davecam48 Friend of Leo's Ad Free Member

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    Gidday young Phil! Just love HHGTTG !!!! I have all the series on disk and still crack up when I listen to them.
    " Life......don't talk to me about life."

    DC
     
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  5. Nick JD

    Nick JD Doctor of Teleocity Ad Free Member

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    Light leaving a light-speed spaceship's headlights leaves at the speed of light to an observer in the spaceship.

    The observer's passage of time is what we need to think about.
     
  6. boyhowdy

    boyhowdy TDPRI Member

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    If it hasn't been pointed out already ...

    The relativistic equations indicate that for a particle moving at the speed of light space contracts to zero as does time.

    This means that from the mover's perspective no time passed and that their beginning location and ending location are the same place.


    Feynman asked the question (jokingly I think) "does the mean there is possibly only 1 photon in the universe?"
     
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  7. Asmith

    Asmith Friend of Leo's

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    I mentioned it's impossible for a particle with mass to travel at the speed of light and can only approach.
     
  8. Toto'sDad

    Toto'sDad Telefied Ad Free Member

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    Why does Light travel? The scientific explanation is that Light got bored, and for a while had the blues, but that was going nowhere, because the blues just keeps you down once you got 'em. Then ol' Light got going on Polka Party dancing, but he couldn't take the accordions anymore, (who could blame him?) then he hooked up with some 50s band, of course that got old, so he finally ended up wearing leathers and doing some really crazy stuff with Schecter guitars which of course didn't last all that long either. At present Light is working his way to Sweden on a tramp steamer since he decided that chasing material things was a bummer, and he left everything behind for a new life. That's why Light travels, he just can't sit still in one place for too long.
     
  9. 1300 E Valencia

    1300 E Valencia Friend of Leo's

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    Only on paper...
     
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  10. srinivassa

    srinivassa Tele-Meister

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    Electromagnetic ether?
     
  11. Larry F

    Larry F Doctor of Teleocity Vendor Member

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    I don't know the answer to this. With sound, air molecules sort of hover in an ambient way. When a force impinges on them, they bang against each other, sort of like they were tennis balls that filled a room. The tennis balls that hit my ear are not the same ones that were on the other side of the room, where the force whacked them.

    Neither my memory not Wiki (not a great place for answers, but sometimes for getting an overview) are making it evident to me that photons don't bang against each other, or just zip down the pike from a flashlight on Mars to my one of my eyes.

    What's the deal with pixels? Why don't we have a sound equivalent of them?

    Light and sound: how are they different? Where does heat figure into this? Help, Mr. Wizard.

    When I was in college, there was a legendary history of science class taught by an old guy who wore a white lab coat. Usually survey classes are taught by younger faculty, because they don't relate much to their research interests, except in a general and maybe inspirational way. They are good to start off with, though, as you get to put together a whole historical overview of a topic, which is kind like a refresher course for the teacher. They help fill in the gaps and give you a more structured understanding of your field.

    But this teacher seemed to have distilled, distilled, and distilled some more the vast historical data and put each topic into 20-minute boxes. It looked as if he had one page of notes for each topic. This helped him boil down the technicalities to their most meaningful and understandable explanations, given the 20-minute self-imposed constraints. An added benefit of the short lessons was that it was easier to connect the work of one scientist with others that came before and after. This format also illustrated the concept of multiple discoveries made by more than one scientist working independently.

    It wasn't a class with much depth, per se, but it was entertaining and useful as hell. I'm sure the teacher's explanation of light and related ideas was as clear and concise as everything else he had in his single pages of notes. I should mention that he didn't recite a list of factoids, but rather told a story with each topic.
     
  12. trev333

    trev333 Telefied Ad Free Member

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    JJ explains it all here..... live

     
    Last edited: May 6, 2016
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  13. boris bubbanov

    boris bubbanov Telefied Ad Free Member

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    Finally, Trev finds the answer. 72 posts.

    Just beat me by 19 minutes!
     
  14. trev333

    trev333 Telefied Ad Free Member

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    ha ha ... I had to look through the whole thread to see if anyone else "got wise" before posting....

    it was the first thing that came to mind reading the title.... ;)
     
  15. J Hog

    J Hog Tele-Holic

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    Why does Light travel? You'd travel too if you were married to Light's wife!!!
     
  16. RoscoeElegante

    RoscoeElegante Friend of Leo's

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    You describing me, or something going on in my 'hood??
     
  17. Ironwolf

    Ironwolf Poster Extraordinaire Gold Supporter

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    Because it's really bad at dribbling.
     
  18. Toto'sDad

    Toto'sDad Telefied Ad Free Member

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    I have reached the conclusion after exhaustive scientific study, and experimentation that light travels because it is afraid of the dark. We will post our conclusions after we conduct similar experiments on why the proverbial chicken crosses the road well traveled. We have no idea why your wife's butt looks bigger in those jeans, but if called upon we will endeavor to provide a reasonable explanation (to us) that may not be entirely satisfying to either, and or any party.
     
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  19. Frank'n'censed

    Frank'n'censed Doctor of Teleocity

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    Why Does Light Travel?

    2016-05-06-16-03-09.jpg
     
  20. JackStraw

    JackStraw Friend of Leo's

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    Cause it's got ramblin' on it's mind?
     
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