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Is light a carrier to bring all the way of motion image of dead star?

  1. Apr 18, 2013 #1
    Hi Friends,

    I am Alen, doing research about light. I have submitted my thesis which contains few finding about light and utilizing maximum solar energy to produce electric energy from few square feet area. I got permission from my adviser to discuss on internet forum. I hope your commands and suggestions will help me in any other ways.

    Now, I would like to give two of them.

    1. Light travels unlimited distance if the source is still alive (later the term "travel" will be replaced by "appear").
    2. Light is not a carrier to bring the image copy of event.

    I hope we can discuss the 2nd point at the moment, it will help me to explain the first point.
    Light is an emission of electron and presence of photon. Photon helps to view the object behind the photon (source) or after it reflects on any object. It just creates a way to see the objects.

    Emitted photon tries to escape from the atom, due to the gravity it absorb by another atom and excess energy cause the emission again and same or new photon release. This is the simple description of light. There should be some loss of energy during the process and it is related to point 1 (discuss later).

    Here I explained my adviser, the source image copy or reflected image copy are not stored frame by frame anywhere in this process. It means whatever we are seeing that happens at the moment of viewing not previous moment copy.

    I tried to explain him that it is related to vision. If we have very powerful telescope and it able to see any faraway galaxy, we can. Since the light of the galaxy is already appeared, we can see it and it not necessary the light to reach us.

    It means we are seeing at the same moment of the happening. If we are seeing a star, it is live at the moment. Light disappear at the same moment when the source of light disappear.

    Please give your points and discuss more.
    Last edited: Apr 18, 2013
  2. jcsd
  3. Apr 18, 2013 #2

    Simon Bridge

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    Welcome to PF;
    That's great - where are you doing the research?
    Is this a PhD thesis then?

    Light already travelling will continue to travel even after the source is long dead too.

    Don't know what "image copy of event" means here.

    Are you trying to describe the photoelectric effect?

    Woah! For gravity to do this, the atom must be a black hole!

    There does not have to be energy loss though. You just won't get a total energy gain.

    Presumably your advisor told you this is not correct - in order to see something with a telescope, light from the object has to pass through the telescope and hit our eyes. Light arriving at our eyes is what allows us to see things.

    The light we see from distant stars started it's journey some time ago. Light from Barnard's star, six light-years away, started it's journey six years ago - this means that we are seeing what the star looked like six years ago. If the star "switched off" somehow right now, we would have to wait six years before we could see it - even with the most powerful telescopes.

    Some of the lights we see in the night sky come from stars which are long dead.
  4. Apr 18, 2013 #3
    Light is just an EM field, the theory is relavistic hence information cannot reach you instantly from a source far away, whenever the source changes you need to wait a certain amount of time for the information to arrive. I don't know what you mean by some of the things you said.
    When the stars emit light, the electromagnetic waves will travel at the speed of light across space and reach us eventually, our eyes are able to measure the frequency and intensity of this wave.
  5. Apr 22, 2013 #4
    I am from Singapore ,completed masters and doing PhD in part time. Actually I am doing business for long time. My intention is not PhD but I don't know where to approach for doing this experiment. So that I joined. My dream is research about light and its in my mind about 20 years. Usually I wont interest in theoretical result. Even if I submitted the thesis, I need experimental result. In fact its required to me to make sure my findings are correct not only for other people. So finally we decided to get help from satellite research centers. We have approached few. I agreed to make the payment from my last year whole income IF any of two fails out of three. I think that's enough now.

    Lets say, there is a full circle of sunspot created on sun. We assume its happened 8 minutes ago, it may or may not be there OR it may be half circle (just for easy conversation) at this moment.

    In this case, we assume as it is half circle sunspot on sun at this moment.

    For us, what we are seeing is 8 minutes ago, so we see full circle of sunspot that appear on sun.

    Now, we are seeing full circle sunspot (created 8 mins ago on sun) where as it is already half circle on sun surface at this moment.

    If we need to see anything, it should be presented somewhere either recorded or real form.

    Just wonder to know, how do we can see the full circle of sunspot since it is not exists on sun? Where from the source of full circle appear to our eyes?

    Additional: Now we have discovered five earth-like planets including 62e, 62f and 69c. It is about 1,200 light-years from Earth.

    Actually I wanted to see the below information and searched google related this article but I am not able to find it:

    "What we are seeing the earth-like planets are presented 1,200 light-years ago, at this moment these may exist there or may not exist there or may have changed something"

    I will update my comments for your other queries.

    I am apologize for the delay reply.
    Last edited: Apr 22, 2013
  6. Apr 22, 2013 #5
    If something is one light year away, when you observe it you will be observing light that was emitted one year ago, electromagnetic waves (light) travel at the speed of light.
    The light reflected off of the exo planets which we observe needs to travel 1200 light years to us, hence it was light that was emitted 1200 years ago. It is possible that the planet might have already been swallowed up in a supernova or something else during this time, if the planet were to explode right at this moment we cannot know about it until 1200 years later.
    I highly recommend learning physics with a textbook instead of raw intuition.
  7. Apr 22, 2013 #6


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    If you are wondering how it is possible to see a full circle of sunspot on the sun as it existed 8 minutes ago when it is now only a half circle, the answer is that the light is in transit. So if you were on Venus and able to view the Sun, you might see the sunspot at 85% circle and if you were on Mercury, you might see it at 70% full circle. Do you understand the concept of light in transit?
  8. Apr 22, 2013 #7

    Simon Bridge

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    @mark.alen: thank you - I look forward to see your replies to my other questions.
    It is puzzling to find someone doing a PhD about light who does not seem to understand the basic facts of the speed of light and how we can see events that have past.

    I can only echo the others here - we cannot see anything until light from the event strikes our eyes or our equipment. It takes time for the light to travel - so we always see events after they have happened. So there is nothing mysterious about being able to see a sunspot that lasts for less than 8 mins just like there is no mystery about hearing the thunder some time after the lighting strike even though the thing causing the thunder has already stopped.
  9. Apr 23, 2013 #8
    That's funny, that's just what long traveling light says, too. :)
  10. Apr 24, 2013 #9

    Simon Bridge

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    The late photon did not apologize for keeping everyone waiting - instead, made light of it.
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