Yup, it is. The only bachelor degrees Cambridge award are BAs, and the degree certificate doesn't even state the subject or class, that's all in some other document called a results transcript.
Anywhere else would have done the sensible thing and changed the title of all the science degrees, but here the attitude seems to be "well no one's complained too much in the last 800 years..."
Not sure which would be better (fortran lets you get away with things that C doesn't, I find I get more runtime bugs), but certainly fortran is still in wide use. I believe that up until last year all Cambridge physics undergrads were still being taught it.
The Feynman lectures are good, and are pretty good at getting you to think about the physics, but are aimed at first year undergrads. I've just completed a BA in maths and I find them interesting, but a little easy.
I'd suggest just googling for course notes for the relevant topics. I'm assuming your vector calculus is already good. Other than that you need to know:
Basic QM
Probably some fluid dynamics
Special and general relativity
Statistical physics / thermodynamics
Some programming experience might also help, Fortran is still in quite common use in physics and is easy to learn.
If you really do want to buy dead trees, I recommend:
Quantum Mechanics by Alastair IM Rae (IOP publishing)
Gravity by James Hartle (Addison-Wesley)
Any of the Landau & Lifshitz books (Butterworth-Heinemann)
They should cover the relevant physics whilst not insulting your intelligence.
Possibly not, a Google search for "Voyager anomaly" did bring up several papers, but I'm not sure how it's related to a non-isotropic universe. It appears to be related to the bow show experienced by Voyager 1.
I have to agree, it is very fascinating. I'm afraid I'm not aware of what the Voyager paradox is, however when we have a lower bound we aren't trying to find a lower one (that wouldn't restrict any further the interval over which we could make such assumptions), we want a bigger lower bound!
I think we're confusing two slightly different terms here. If they all point the same way it is most definitely not "isotropic," as there is clearly something different about that direction. If, however, as you move through the galaxy you find that the direction the galaxies are locally pointing does not change, it's still "homogeneous."
Huh. I don't really have a great deal of specialist knowledge on cosmology, but this seems to put a lower bound on the distance over which we can assume the universe is isotropic (i.e. the same in all directions). The abstracts puts an upper bound on the redshift of the galaxies involved in the survey, which is presumably roughly equivalent to limiting the distance they are from us, but surely the fact that this net angular momentum axis is closely aligned with an axis identified in WMAP data indicates that this is a far larger scale phenomenon?
To anyone who's got this far without having downloaded the mp3, go listen to it! It is actually quite interesting.
And to anyone who's ever been lectured by Turok, don't worry, he isn't that bad when he's actually interested in what he's talking about...
That's not quite true. An autopilot can fly a very good flight path provided all the nav radios etc are working, but it lacks a decent pair of eyes. With only an autopilot there's nothing to stop you having a collision with a stay light aircraft, or a jumbo with a broken transponder. It also can't "think on its feet" if something goes wrong.
This just goes to show, not matter how much you warn people they're about to do something really dumb, the still will. How many people do you think read that advert, though "No, it can't possibly mean that..." and then clicked on it to see?
Want to do something about this? If you're a UK citizen go sign the petition. From past form it appears that the government will ignore it, but the BBC sometimes reports those that get enough signatures.
Recently I read a news article saying that the Royal Navy were considering outfitting their next generation of carriers (which will actually be proper carriers rather than "through-deck cruisers") with French aircraft instead of the F-35B, due to the US's refusal to grant access to the source code for the F-35B's software. Anyone think they're going to be a lot more eager to get their hands on the source code now?
Shepard's flight was made in a Mercury capsule, as was Glenn's. It was an orbital capable vehicle. Also the fact that it was a capsule meant adding more fuel capacity was simple, mount it on a larger booster.
Spaceship One is not a vehicle capable of orbit. Nor is it or any closely related variant ever likely to be. It does not carry anywhere near enough fuel to get it into orbit, and White Knight can't reach sufficiently high speeds to put it in orbit with the fuel it carries. It does not have a sufficiently substantial heat shield to return from orbit.
The Russians did not develop a sub-orbital Vostok because they had a sufficiently powerful booster to put it into orbit. Again, we have the advantage of a capsule over a plane. You can strap a bigger booster onto a capsule. You can't on a plane.
In the meantime, expect China to be counting down the days until it can start shooting down all our satellites that pass over it without fear of a shuttle going up there to figure out what happened.
A shuttle is not necessary to determine that a satellite has been destroyed by a missile. The destruction of China's weather satellite was reported before China confirmed the test had taken place. And I'm pretty sure that no shuttle went to have a look.
If I were China, I know I would.
Then you would be very foolish. The US is hardly space's greatest pacifist. Any attack on a US satellite would bring some form of reprisal from the US, whether it be a shoot-down of a Chinese satellite (the US has developed the teachnology to do so in the past) or economic sanctions.
Because a government agency, funded by public money, would be offering a commercial service that would be beyond the financial means of all but a very small segment of the population.
Places on manned NASA flights should be strictly determined by the benefit an individual would impart to the flight either by scientific work in orbit or by ability as a crew member of the launch vehicle. The size of the afformentioned individual's bank account should not be a factor.
There seems to be a lot of rather confused postings regarding the capabilities of the private sector in space. Virtually every commercial launch system has had large amounts of government input in some form or another. Even SpaceX used some government facilities. As for manned space flight, Scaled Composites flight was nowhere close to real space flight. They flew into space, they didn't really fly in space. Orbital, manned flight is a far more complicated affair requiring experience that no private company possess currently.
NASA is a government agency, the purpose of which is to advance science in the fields of astrophysics, spaceflight and aeronautics. It does not exist to offer a commercial service to members of the public who wish to travel into space for recreation. To do so would be to give unfair privilege to the wealthy, and would take up time and payload capacity which could be better used for other purposes. If NASA is having trouble funding its operations, that would suggest that its budget is insufficent, and needs increasing. Were the Bush administration not to have gone tax-cut-happy the moment it came to power, NASA might have slightly more resources at its disposal.
However, the problem here seems to be partly developmental as well as funding based. If I recall correctly, a gap between the shuttle's retirement and the CEV's first launch was expected, just not of this duration.
I disagree. Whilst shuttle saftey could be improved by newer vehicles, the design in general just isn't safe, it doesn't allow for any reasonable launch escape system. The ejector seats that were fitted for the first few flights are impractical do to the very small section of the flight envelope in which they can be used, and the fact that several crew members are in the lower deck, making ejection impossible for them. The only abort modes of flight still require the boosters to run their course and then be jetissoned.
Dude, I really hope you mean for (forgetting password to / deleting) you PGP key. You're saying I actually have to remember my whole PGP key? I have trouble remembering my own telephone number!
Your figure could be correct. Using data from Wikipedia for a Boeing 747-400, we have a cruise speed of 913 km/h = 253.6 m/s, and a maximum weight of 396890kg giving a fully loaded aircraft in flight a momentum of 1.01x10^8 kg m s^-1. However the empty weight is less than half this figure, so a lightly loaded 747 flying slowly could have a momentum of 4.1x10^7 kg m s^-1.
What is wrong though is your unit and your term "impulsive force". Impulse (which is indeed what we should be talking about when we want to bring a moving body to rest) is the time integral of force, and has units of Newton seconds, not Newtons.
And yes, I would prefer 1.01x10^8 Ns to "can stop a 747."
Slashdot Mirror
Yup, it is. The only bachelor degrees Cambridge award are BAs, and the degree certificate doesn't even state the subject or class, that's all in some other document called a results transcript.
Anywhere else would have done the sensible thing and changed the title of all the science degrees, but here the attitude seems to be "well no one's complained too much in the last 800 years..."
Not sure which would be better (fortran lets you get away with things that C doesn't, I find I get more runtime bugs), but certainly fortran is still in wide use. I believe that up until last year all Cambridge physics undergrads were still being taught it.
Good point about EM.
And who's Jackson?
The Feynman lectures are good, and are pretty good at getting you to think about the physics, but are aimed at first year undergrads. I've just completed a BA in maths and I find them interesting, but a little easy.
I'd suggest just googling for course notes for the relevant topics. I'm assuming your vector calculus is already good. Other than that you need to know:
Basic QM
Probably some fluid dynamics
Special and general relativity
Statistical physics / thermodynamics
Some programming experience might also help, Fortran is still in quite common use in physics and is easy to learn.
If you really do want to buy dead trees, I recommend:
Quantum Mechanics by Alastair IM Rae (IOP publishing)
Gravity by James Hartle (Addison-Wesley)
Any of the Landau & Lifshitz books (Butterworth-Heinemann)
They should cover the relevant physics whilst not insulting your intelligence.
Possibly not, a Google search for "Voyager anomaly" did bring up several papers, but I'm not sure how it's related to a non-isotropic universe. It appears to be related to the bow show experienced by Voyager 1.
I have to agree, it is very fascinating. I'm afraid I'm not aware of what the Voyager paradox is, however when we have a lower bound we aren't trying to find a lower one (that wouldn't restrict any further the interval over which we could make such assumptions), we want a bigger lower bound!
I think we're confusing two slightly different terms here. If they all point the same way it is most definitely not "isotropic," as there is clearly something different about that direction. If, however, as you move through the galaxy you find that the direction the galaxies are locally pointing does not change, it's still "homogeneous."
Huh. I don't really have a great deal of specialist knowledge on cosmology, but this seems to put a lower bound on the distance over which we can assume the universe is isotropic (i.e. the same in all directions). The abstracts puts an upper bound on the redshift of the galaxies involved in the survey, which is presumably roughly equivalent to limiting the distance they are from us, but surely the fact that this net angular momentum axis is closely aligned with an axis identified in WMAP data indicates that this is a far larger scale phenomenon?
To anyone who's got this far without having downloaded the mp3, go listen to it! It is actually quite interesting. And to anyone who's ever been lectured by Turok, don't worry, he isn't that bad when he's actually interested in what he's talking about...
That's not quite true. An autopilot can fly a very good flight path provided all the nav radios etc are working, but it lacks a decent pair of eyes. With only an autopilot there's nothing to stop you having a collision with a stay light aircraft, or a jumbo with a broken transponder. It also can't "think on its feet" if something goes wrong.
In Soviet Russia, ice melts YOU!
This just goes to show, not matter how much you warn people they're about to do something really dumb, the still will. How many people do you think read that advert, though "No, it can't possibly mean that..." and then clicked on it to see?
Except that your extra horsepower is constantly being used to drag around your huge SUV that you somehow believe is compensating for your small penis.
One that lacks a basic understanding of electromagnetism.
Want to do something about this? If you're a UK citizen go sign the petition. From past form it appears that the government will ignore it, but the BBC sometimes reports those that get enough signatures.
Recently I read a news article saying that the Royal Navy were considering outfitting their next generation of carriers (which will actually be proper carriers rather than "through-deck cruisers") with French aircraft instead of the F-35B, due to the US's refusal to grant access to the source code for the F-35B's software. Anyone think they're going to be a lot more eager to get their hands on the source code now?
The shuttle is effectively a rocket during launch. Its wings are not providing any lift. This is not the case with space ship one.
Shepard's flight was made in a Mercury capsule, as was Glenn's. It was an orbital capable vehicle. Also the fact that it was a capsule meant adding more fuel capacity was simple, mount it on a larger booster.
Spaceship One is not a vehicle capable of orbit. Nor is it or any closely related variant ever likely to be. It does not carry anywhere near enough fuel to get it into orbit, and White Knight can't reach sufficiently high speeds to put it in orbit with the fuel it carries. It does not have a sufficiently substantial heat shield to return from orbit.
The Russians did not develop a sub-orbital Vostok because they had a sufficiently powerful booster to put it into orbit. Again, we have the advantage of a capsule over a plane. You can strap a bigger booster onto a capsule. You can't on a plane.
In the meantime, expect China to be counting down the days until it can start shooting down all our satellites that pass over it without fear of a shuttle going up there to figure out what happened.
A shuttle is not necessary to determine that a satellite has been destroyed by a missile. The destruction of China's weather satellite was reported before China confirmed the test had taken place. And I'm pretty sure that no shuttle went to have a look.
If I were China, I know I would.
Then you would be very foolish. The US is hardly space's greatest pacifist. Any attack on a US satellite would bring some form of reprisal from the US, whether it be a shoot-down of a Chinese satellite (the US has developed the teachnology to do so in the past) or economic sanctions.
Because a government agency, funded by public money, would be offering a commercial service that would be beyond the financial means of all but a very small segment of the population.
Places on manned NASA flights should be strictly determined by the benefit an individual would impart to the flight either by scientific work in orbit or by ability as a crew member of the launch vehicle. The size of the afformentioned individual's bank account should not be a factor.
There seems to be a lot of rather confused postings regarding the capabilities of the private sector in space. Virtually every commercial launch system has had large amounts of government input in some form or another. Even SpaceX used some government facilities. As for manned space flight, Scaled Composites flight was nowhere close to real space flight. They flew into space, they didn't really fly in space. Orbital, manned flight is a far more complicated affair requiring experience that no private company possess currently.
NASA is a government agency, the purpose of which is to advance science in the fields of astrophysics, spaceflight and aeronautics. It does not exist to offer a commercial service to members of the public who wish to travel into space for recreation. To do so would be to give unfair privilege to the wealthy, and would take up time and payload capacity which could be better used for other purposes. If NASA is having trouble funding its operations, that would suggest that its budget is insufficent, and needs increasing. Were the Bush administration not to have gone tax-cut-happy the moment it came to power, NASA might have slightly more resources at its disposal.
However, the problem here seems to be partly developmental as well as funding based. If I recall correctly, a gap between the shuttle's retirement and the CEV's first launch was expected, just not of this duration.
I disagree. Whilst shuttle saftey could be improved by newer vehicles, the design in general just isn't safe, it doesn't allow for any reasonable launch escape system. The ejector seats that were fitted for the first few flights are impractical do to the very small section of the flight envelope in which they can be used, and the fact that several crew members are in the lower deck, making ejection impossible for them. The only abort modes of flight still require the boosters to run their course and then be jetissoned.
Dude, I really hope you mean for (forgetting password to / deleting) you PGP key. You're saying I actually have to remember my whole PGP key? I have trouble remembering my own telephone number!
Your figure could be correct. Using data from Wikipedia for a Boeing 747-400, we have a cruise speed of 913 km/h = 253.6 m/s, and a maximum weight of 396890kg giving a fully loaded aircraft in flight a momentum of 1.01x10^8 kg m s^-1. However the empty weight is less than half this figure, so a lightly loaded 747 flying slowly could have a momentum of 4.1x10^7 kg m s^-1.
What is wrong though is your unit and your term "impulsive force". Impulse (which is indeed what we should be talking about when we want to bring a moving body to rest) is the time integral of force, and has units of Newton seconds, not Newtons.
And yes, I would prefer 1.01x10^8 Ns to "can stop a 747."