Astrophysics/Questions Answered by Expert James Gort
| Subject | Date Asked |
| Black Hole - Holographic Principle | 12/23/2011 |
| Q: The holographic black hole principle sounds like a record or dvd full of information but when ... A: I'm afraid I don't agree or disagree with the Holographic Principle. I just don't know, and from ... | |
| comets and Jupiter | 12/20/2011 |
| Q: James, I've heard many times about the high percentage of comets that have not hit the earth due to ... A: The main compelling evidence for the asteroid theory seems to be the widespread bombardment at the ... | |
| comets and Jupiter | 12/19/2011 |
| Q: James, I've heard many times about the high percentage of comets that have not hit the earth due to ... A: Very interesting question! But until recently, little research was done to back up the claim that ... | |
| Expanding universe | 12/9/2011 |
| Q: I know that the universe is expanding at an accelerating rate. Will the speed of the expansion ever ... A: First, I know some Nobel Prizes were awarded for the "discovery" of the accelerating universe. So I ... | |
| venus | 12/5/2011 |
| Q: I have read that in the craters of venus ice has been detected. Is this true? A: No, there's no liquid water or ice. The surface temperature is several hundred degrees. Some ... | |
| physics | 12/3/2011 |
| Q: sir why the value of g gets changed when it suddenly stops spinning?and sir by any mean can the ... A: An object which is spinning is in an accelerating reference frame. "g" is the "gravitational ... | |
| Gliese 581 | 10/30/2011 |
| Q: Dr. Gort, Although I am not formally educated, I am, like many others, a fan of cosmology. I am ... A: Although your son may eventually be able to get there, please explain to him that we'll have to ... | |
| speed of light | 9/6/2011 |
| Q: It is said that nothing,even information,can exceed the speed of light in this universe.However if ... A: What you're missing is that no rod is truly "rigid". For instance, steel has a carbon and iron ... | |
| Cosmological Expansion or Transition? | 8/19/2011 |
| Q: Is the Hobble observation conclusive evidence that our universe is expanding? Would there be an ... A: Yes, I think there would be an observable difference, but let me go through your scenario: If a ... | |
| scientific notation | 8/17/2011 |
| Q: My basic question is if it okay to write scientific notstion without using superscripts. For example ... A: There are basically three ways that I know of. But there should be a footnote or other explanation ... | |
| Astronomy | 5/4/2011 |
| Q: I want to know that what will happen if Two Neutron stars or Two Black holes or a Neutron star and a ... A: If two neutron stars, two black holes, or a neutron star and a black hole came close to each other ... | |
| hadron collider | 1/11/2011 |
| Q: my question is could the hadron collider be causing all the bird and fish deaths. Could it be doing ... A: The Super Hadron Collider was the cause of some concern by some people - such as possibly creating ... | |
| speed of light | 9/4/2010 |
| Q: If two beams of light are aimed at one another, is the closing speed twice the speed of light? A: If two beams of light are aimed at each other, their closing speed would be the speed of light! I ... | |
| Matter | 4/12/2010 |
| Q: I'm not sure if this is the correct field, but are there any theories as to how matter first ... A: The best (and really only) explanation for the creation of matter (the big bang) that I've read was ... | |
| Big Bang Theory | 4/10/2010 |
| Q: I do not know much about the Big Bang Theory, but I was hoping that you might be able to explain to ... A: First of all, I want to remind you that the origin of the universe by a "Big Bang" is very much ... | |
| entropy and the accelerating expansion | 4/2/2010 |
| Q: I am a 38-year-old student of popular science. I don't understand much math, but I am very ... A: Very interesting question. And one that's the subject of some recent research. According to some, ... | |
| LHC Probing the Improbable | 1/22/2009 |
| Q: I had this article delivered in my mail today and I'm rather concerned on what is stated here! Would ... A: First, thanks very much for that link. My first impression is that there's a lot of pages to state ... | |
| extrasolar spectrum | 1/20/2009 |
| Q: Gort, thanks for making yourself available. I teach art in Philadelphia. Our sun appears yellow ... A: Yes, our sun is indeed yellow, but not "very' yellow. Its light is comprised of all the colors in ... | |
| right ascension and declination | 1/4/2009 |
| Q: can you tell me how to first convert an example: 0hours 8min. 23.2 seconds to degrees for right ... A: The easiest way is to set up ratios. For example, there are 60 seconds in a minute and 60 minutes ... | |
| Why sky is dark? | 5/2/2008 |
| Q: i have heard that sky is dark because universe is young.that's why light from distant star has not ... A: While it is true that some stars are forming at distances such that their light has not yet reached ... | |
| Fermi acceleration | 4/22/2008 |
| Q: Can you explain a bit about how Fermi acceleration works and how one can best quantify it? Thanks! A: This is a difficult one. I'm not sure on your background in physics. So my answer might be too ... | |
| gravitation | 9/14/2007 |
| Q: can you explain the universal law of gravitation? A: Sir Isaac Newton first wrote down the universal law of gravitation, saying that any two masses ... | |
| Colapsing Universe | 9/13/2007 |
| Q: I gave it a bit more thought to the imaginary universe which you so elegantly explained to me, when ... A: I think the rules also need to account for photon emission. For instance, in thermodynamic ... | |
| planets | 5/29/2007 |
| Q: how many stars appears in our sky? A: In any one night, we could see about 6000 stars with the naked eye. But there are about 100 billion ... | |
| planet x | 5/29/2007 |
| Q: what do you know about the new planet x? A: You're probably referring to the discovery in April of an "earth-like" planet about 20 light-years ... | |
| Speed of light | 5/27/2007 |
| Q: The Science says that if you travel to the nearest stars at the the speed of light time will seem ... A: Yes, if the distance is shorter, less time will have elapsed. If you travelled to a star 10 ... | |
| Light | 5/22/2007 |
| Q: What happens to light once its source stops producing it, e.g. when a candle is blown out? Also, ... A: When a candle is lit (or a laser is turned on), some of the chemical energy (or electrical energy in ... | |
| accretion disk around a black hole binary | 5/8/2007 |
| Q: .. I'm struggling on another that I hope you can give me a hand with. The question is: This problem ... A: 1) Without plugging in actual numbers, I would guess that your graph has the right form. For ... | |
| Vector Mechanics | 5/7/2007 |
| Q: I've been looking at vector mechanics applied to phycical problems and I am stuck on one aspect ... A: Scalar products are actually easier to understand than cross products. The definition of a scalar ... | |
| Speed of Light - Special Relativity Postulate | 4/27/2007 |
| Q: I have a degree in Physics with Astrophysics, and enjoyed and understood everything that I was ... A: It certainly helps in formulating the answer! 1) Let's start with Newtonian mechanics. If A is ... | |
| Wind due to acceleration of earth? | 4/25/2007 |
| Q: I'm not really sure what subject area this question falls into but I figured astrophysics is a good ... A: That's an interesting problem. Let me begin with your stated hypothesis - no temperature or ... | |
| Eddington Limit | 4/16/2007 |
| Q: How are you? Very well I hope! I have a problem that I really need a little hint on if you don't ... A: Looks like a good problem! OK, I'll give some hints: I'm not sure why you mention Wien's Law. ... | |
| Geometery/dimensions/matter displacement | 2/28/2007 |
| Q: Greetings Professor. I hope I'm not monopolizing your time. I appreciate the answer you gave to my ... A: No problem on the time. I see you've been thinking this through! First, answers to some of your ... | |
| space time | 2/27/2007 |
| Q: Does time stop when you reach the boundary of the finite universe? If the universe was a ... A: Yes, you could say that "time stops" outside of the space-time boundary of the universe, in the ... | |
| MOVE | 1/26/2007 |
| Q: Why do molecules in a solid move more slowly thanb tthose in a liquid? What is it about the ... A: To answer your question properly, I need to explain the states of matter and the reason for solids, ... | |
| Anti_matter | 1/15/2007 |
| Q: Does anti-matter fall up or down? A: Anti-matter falls down. Although many properties of anti-matter are the opposite of ordinary ... | |
| Stopping_light | 1/15/2007 |
| Q: Can light be stopped? If yes, the how? A: No, light cannot be stopped. It can only be absorbed and emitted. Even reflection of light is not ... | |
| seeking a mathamatical concept... | 1/8/2007 |
| Q: i love the fact that the world is mathamatical. i would like a tatto or tattos of mathamatical ... A: I've given this considerable thought. Since mathematical concepts are usually expressed in the form ... | |
| Universe. | 12/19/2006 |
| Q: How would a photon behave in a universe where all dimensions are collapsing at the speed of light? A: I'll give you my best guess on this one. It's certainly an interesting question! According to ... | |
James Gort
Top Expert on this page
Expertise
Questions on observational astronomy, optics, and astrophysics. Specializing in the evolution of stars, variable stars, supernovae, neuton stars/pulsars, black holes, quasars, and cosmology.
Experience
I was a professional astronomer (University of Texas, McDonald Observatory), lecturer at the Adler Planetarium, professor of astrophysics, and amateur astronomer for 42 years. I have made numerous telescopes, and I am currently building one of the largest private observatories in Canada.
Publications
StarDate, University of Texas, numerous Journal Publications
Education/Credentials
B.A. Physics and Astronomy
M.Sc. Physics
Ph.D. Astrophysics
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