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Lv 55,263 points

Robert321

最佳解答17%
解答961
  • At what size does a planet cease to be described as a planet.?

    If The Earth is compressed, without loss of mass - at what point does it stop being described as a planet?

    4 個解答Astronomy & Space6 年前
  • We can never out run the light we see?

    We can never out run the light we see. (c)

    However it is conceivable that we could travel much faster than 299 792 458 meters / second.

    The current understanding in this matter (by almost all) is incorrect.

    At first glance it would appear even Einstein was (shall we say) "a little wobbly."

    Can any of you guys : show me I'm wrong?

    11 個解答Astronomy & Space7 年前
  • Aether v Spacetime PS : you may say it out loud ...AETHER! See...ostracised, but no leprosy.?

    Is Einstein's Spacetime just another description of Ether. (Aether)

    Spacetime, cosmological constant, quintessence, vacuum energy, quantum foam, Higgs field : aren't they all just alternative descriptions / forms of an "aether"? Without which there could be no General Relativity.

    Did not Einstein himself make such a suggestion?

    7 個解答Astronomy & Space7 年前
  • The Universe as viewed by mathematicians?

    I just read an answer to a question about parallel universe here :

    http://ca.answers.yahoo.com/question/index;_ylt=Ao...

    In R Bs answer I found this quote:

    // "Nothing in reality exists contrary to mathematics; so if the math says it doesn't exist then it doesn't exist in reality as well; End of Story period !!!" //

    .

    I'm hopeless at math so I'm wondering : when it comes to the problems of infinities and singularities within mathematics, how do mathematicians view these problems in the "real world"?

    Do mathematicians believe infinities and singularities exist in the real physical universe?

    5 個解答Astronomy & Space8 年前
  • Big_Bang v Redshift interpretation?

    Disregarding Doppler effect and Cosmological Red shift.

    What other evidence points toward / collaborates, or is in favour of / The Big Bang theory.

    Simply : Is Big Bang theory entirely based on the currently accepted understanding of Redshifts?.

    Links; would be much appreciated.

    3 個解答Astronomy & Space8 年前
  • Expanding Universe : Cosmological redshift?

    Disregarding Cosmological Red shift.

    What other evidence points toward / collaborates, or is in favour of / the expansion of the Universe and the increasing rate thereof?

    Links; would be much appreciated.

    7 個解答Astronomy & Space8 年前
  • Pseudoscience. Predictions are regarded as pseudo science?

    Predictions are regarded as pseudo science but if ones predictions in the future continually prove to be accurate. Is the predictor :

    A. Extremely lucky at guessing.

    B. From the future.

    C. A visionary

    D. Other.

    Example : I predict; In the very near future most bone / joint afflictions, in particular: Rheumatoid arthritis and sciatica will be directly linked to the use of antibiotics, of course it's not the antibiotics themselves which are the problem, rather it's the eradication of all bacterium, and its subsequent replacement with the "guilty" bacterium.

    In addition : an advancement in research ( human papillomavirus HPV - based research ) into viruses will soon; result in a connection between viral infection and up to 80% of cancers, further research will lead to anti viral inoculation from said cancers.

    .

    Predicting the future is pseudo science: but when all of this comes to be "and I believe it will".

    Would it then be described as pseudo science? Or would it then be described as scientific breakthrough foreseen by A, B, C, or D.

    1 個解答Other - Social Science8 年前
  • Olbers' Paradox and Cosmic microwave background radiation?

    Could the CMBR be equivalent to an Olbers' effect?

    .

    Olbers ' Paradox :

    http://en.wikipedia.org/wiki/Olbers'_par%E2%80%A6

    Firstly : I don't believe there is a Paradox!

    Explanation :

    Without the need to include cycles (Stars /Galaxies and their life and death) Olbers ' Paradox presumes us to have eyesight far superior to that which we really have.

    For instance : place a candle 80km distance, there's no way you're going to see it, there's simply not enough photons going to reach your eye in order to register light, adding multiple candles at large area separation isn't going to make a great deal of difference, you're still not going to see them.

    Our visual ability is self evident - "If it's too far we can't see it with naked eye" - the night sky simply reveals that which; is close enough and/or luminous enough for the naked eye to register.

    We see dark sky: because we are limited in our visual ability to perceive relatively small points at great distances, Andromeda Galaxy is about as far as we can see but we all know it is - but one - of countless millions, billions of Galaxies : the distribution /concentration of galaxies per area: is "as is"

    this; is no indication on whether the amount of Galaxies beyond our field of vision is finite or infinite.

    .

    Park a car with headlights on at 1km distance, another car each side, maybe 100 meters from first car (visually, in line of sight) but at 10 km more distant (headlights on) another two at 100km and again at 1000 km and so on.

    First cars lights are easily seen, proximity of second car means; the lights of the first car reduce the ability to see the Second cars lights ( even though it's only 10 km distant ) : further car hadilghts would be beyond register of naked eye because of distance and light interference from closer cars.

    .

    .

    .

    An infinite universe would look no brighter from Earth than a finite universe. The farther Galaxies with their given brightness : are "obviously" out there; we simply can't see them with naked eye because of the great distances involved : hence; the sky at night is dark.

    Now: If you could increase your eyes magnification to the level required to confirm "Olbers effect" :

    Would it? In fact, be seen.

    It may well be so.

    .

    Take the darkest most empty patch of night sky, with a good enough telescope you will observe hundreds of bright Galaxies : The Hubble telescope extended enormously this very point: to reveal a multitude of Galaxies.

    You - hopefully- now see that these observations from Earth or Hubble have no bearing on the question of whether the Universe is finite or infinite.

    BUT :

    .

    .

    The Olbers Paradox "effect" could indeed be very similar to an effect we have come to know as :

    .

    .

    .

    THE COSMIC MICROWAVE BACKGROUND RADIATION.

    http://en.wikipedia.org/wiki/Cosmic_micr%E2%80%A6

    .

    .

    Question:

    With Hubble telescope as "the observer"

    Can you describe the differences between an Olbers' Paradox "effect"and the CMBR?

    .

    All the best.

    7 個解答Astronomy & Space8 年前
  • Inflationary_theory. Why did it slow?

    Once the inflationary phase begins and is "in motion" what caused / triggered that rate of motion (rapid expansion) to then slow?

    Why? When there existed nothing to slow the rate of inflation, did the inflation not persist?

    3 個解答Astronomy & Space8 年前
  • Big Bang question . .?

    In Big Bang theory : as we go back in time toward the original event, everything was closer and denser, but does this actually mean that very early in the "life" of the universe, it's radius would have been less than one light year, earlier still, less than one metre, and so on?

    If yes, would this indicate, the area we (The Milky Way) occupies, was long ago part of the so called " void " of nothingness and only later acquired "spacetime"? Or ( current understanding, I think) did the space we now occupy always exist within the early "metres" and was carried with inflation / expansion to where we are now?

    .

    Sorry, that doesn't read very well.

    6 個解答Astronomy & Space8 年前
  • Hollow sphere = zero internal gravity.?

    This is a continuation of a question asked by Sammy : - - -"If there was a hollow sphere the size of Earth floating through space, where would the gravity be the highest?

    The shell is made of iron, a meter thick. The inside is just vacuum like the outside. @

    http://uk.answers.yahoo.com/question/index?qid=201... - - -

    .

    My question :

    . ..Assuming such a sphere could be stable and has no rotation, now imagine, a glass marble inside the sphere, one kilometre from centre point, no initial rotation or motion.

    The hollow sphere has no gravity. ( current understanding. ) I don't seem to be able to get my head round this, I keep seeing the iron sphere (has mass) as having a gravitational effect inside the hollow, thus the marble tends toward the inner surface of the shell and if I do manage to block this from my mind, the marble tends toward the centre point.

    How does the marble behave? Does it stay stationary? Or what? Any ideas? Or does anyone know what actually would happen to the marble?

    7 個解答Astronomy & Space8 年前
  • In a dream, an Entity which you believe to be God, Allah, or?

    In a dream, an Entity which you believe to be God, Allah, Pamela Anderson who ever you believe in reaches into your drawer and lift your Bible, Koran, playboy, whatever, places a hand on the cover then returns said book to the drawer, saying only one word "wisdom" at which the dream ends and you awaken.

    Instantly feeling rushed with adrenaline you retrieve the book from the drawer, the cover has changed and now displays only one word "Life" on reading you find the contents are of every event in your life, the emotions times and dates, from the shock of the cold dry air on your hot wet body as you were born, till present day, everything detailed.

    The last Page contains a sealed envelope with the word "Death" and in small lettering underneath are the words "herein lays the date of the apocalypse, you shall die immediately before this date."

    Would you open the envelope?

    Would you share the date with others?

    2 個解答Religion & Spirituality8 年前
  • Galaxy distribution, compare fields?

    Does Galaxy distribution change with distance?

    Are the Galaxy's closer / farther apart from their neighbours when we look to Hubble Deep Field than they are compared to HUDF or HXDF?

    4 個解答Astronomy & Space8 年前
  • Mabus. Nostradamus. 2 / 62?

    Soon Mabus will die, and then will come

    A terrible undoing of animals and people

    Suddenly, vengeance will appear

    In the form of a comet; hunger,thirst, a hundred hands.

    Where does Nostradamus mention 'Mabus' as being evil, or the third antichrist?

    5 個解答Religion & Spirituality8 年前
  • Length contraction v nature.?

    If I'm travelling at speed nearing light speed, the length of an body, eg, the planet Earth, will be shortened / contracted in the direction parallel to which I'm travelling, at very close to 'c' the mass of matter we call "Earth" would be flattened to resemble a disc, at no point during this flattening does the Earth's radius increase.

    My question. Is there anywhere in nature where mass is flattened without increase in radius / area?

    4 個解答Astronomy & Space8 年前
  • Revelation 13, 18. The number of the beast. (666)?

    Revelation 13, 18. The number of the beast. (666) . counted.

    Here is wisdom. Let him that hath understanding count the number of the beast :

    For it is the number of a man; And his number is Six hundred three score and six.

    The words 'here is wisdom' are they to indicate that wisdom lays with he who understands? or is, 'here is wisdom' written as a message to the finder, perhaps indicating he should use wisdom before revealing or not, that which he has found?

    Or does it mean something else?

    10 個解答Religion & Spirituality8 年前
  • Length contraction : Physical or visual?

    I keep imaging this as being just visual.

    In length contraction :

    http://en.wikipedia.org/wiki/Length_contraction :

    When approaching light speeds, is the contraction physical does the ruler / rocket, etc actually shrink in length? or is the shrinking a visual perception?

    4 個解答Astronomy & Space8 年前