Escaping a black hole is fairly easy because of the photon flux from the accretion disk. You get lots of radiation pressure pushing you away. If the power level drops just drop in a small amount of matter.
Say you find out on 1 Jan 2011 that the Earth will be swallowed by a brand new black hole on 1 Jan 2111. You spend the next 100 years working to move the human race to Mars and building new infrastructure there to support them. That 100 years of effort has a finite value which could be calculated. That way you know the cost of destroying the Earth.
the Earth has been--and continues to be--bombarded by cosmic rays of immensely greater energies than found in the LHC.
But those cosmic rays have high velocity and kinetic energy. A cosmic ray (so to speak) created at rest in France would have different properties. It may be trapped in orbit around the Earth. Maybe the greater energy of cosmic rays from space makes them safer for us.
When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
Arthur C Clarke would have loved this debate BTW. I am sorry he can't be here. I am off to read Childhoods End again.
If you make a tiny black hole you start a race between evaporation and accretion. The black hole may well evaporate before it collects enough mass to be stable, but it is difficult to be completely sure about this. In theory the black hole can start from the mass of an atom and increase in mass to the mass of the Earth (plus us of course).
Old story. Back in the days when dumb computer terminals were a new idea a museum had one set up so that people could play with it. Typing words, etc. Of course school groups would come through and it would get covered with rude words so some bright spark wrote a program to filter out the rude words.
Everybody was happy until a bright young geek in a school group saw the flaw in the system. The filtering program had to have a management interface with a way to display the banned list. If that interface could be found much typing could be saved and much embarrassment created...
The big flaw in the filter is that nobody can ever know what is being filtered, otherwise bypassing the filter can be made trivial and the filter will its self be a handy list of nasty stuff for people to go to. So if the filter ever becomes a political tool there will be no easy way for the public to find out. I think this flaw should be pushed as the most important problem in the system.
In 1997 in Galway, Ireland I watched the Army deliver money to a bank. They don't use security guards for that in Ireland. Or didn't, anyway. They had three guys in good positions with self loading rifles triangulated on the entrance to the bank. There were hundreds of people in the street and if they had opened up with the guns many people would have died.
Money and explosives are taken very seriously in Ireland.
TFA doesn't explain why the explosives were planted. One obvious reason is to test security but in that case you would have a "wicket keeper" to catch the undetected explosives.
I recall reading about police in (I think) Japan who were doing this with drugs. Planting the stuff on people then testing their inspectors. One sample got away I believe.
I expected security tests with planted explosives to come at some point, but I assumed that they would use undercover agents to test security, not innocent bystanders. However, I'd assumed the same would have happened for something like the described drug operation in Japan. I don't see how any government could do something so reckless.
They are doing a proper double blind test. The Undercover agents would give away their special status. A lot of the work of security is watching the behaviour of the travelling public. Does this person think like a bored traveller?
TFA doesn't explain why the explosives were planted. One obvious reason is to test security but in that case you would have a "wicket keeper" to catch the undetected explosives.
I recall reading about police in (I think) Japan who were doing this with drugs. Planting the stuff on people then testing their inspectors. One sample got away I believe.
The biggest mistake we make about climate change is to think of it as a short term issue. Its not. You can't look at the climate over a year or a decade and make statements about global climate change.
So yeah it is a security issue, but on the scale of the next 50 or 100 years. I don't think it is appropriate for the CIA to work on issues over that time scale.
Having said that, the CIA apparently has remote sensing assets which can contribute to the long term picture of global climate. Using data from those assets in other domains is appropriate.
My understanding of cosmology is at best limited, but shouldn't these galaxies appear red-shifted to the extreme? They are furthest and hence should be moving the away from us at an extremely fast pace. Is the name Ultra-blue restricted to element analysis based on spectrum? I'm just confused about the blue light.
Looking at this bit:
They are so blue that they must be extremely deficient in heavy elements, thus representing a population that has nearly primordial characteristics."
I assume this means that light, hydrogen-heavy objects will get hotter for a given amount of heat energy because of their lower density. Maybe these galaxies are red shifted, but they are relatively blue in relation to their red shift.
Slashdot Mirror
Escaping a black hole is fairly easy because of the photon flux from the accretion disk. You get lots of radiation pressure pushing you away. If the power level drops just drop in a small amount of matter.
Say you find out on 1 Jan 2011 that the Earth will be swallowed by a brand new black hole on 1 Jan 2111. You spend the next 100 years working to move the human race to Mars and building new infrastructure there to support them. That 100 years of effort has a finite value which could be calculated. That way you know the cost of destroying the Earth.
Whoa there bucko. Sweden is next to France?!
With a big enough black hole I could "make it so".
the Earth has been--and continues to be--bombarded by cosmic rays of immensely greater energies than found in the LHC.
But those cosmic rays have high velocity and kinetic energy. A cosmic ray (so to speak) created at rest in France would have different properties. It may be trapped in orbit around the Earth. Maybe the greater energy of cosmic rays from space makes them safer for us.
Brian Cox: "Anyone who thinks the LHC will destroy the world is a twat."
To which I will invoke Clarke's first law:
When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
Arthur C Clarke would have loved this debate BTW. I am sorry he can't be here. I am off to read Childhoods End again.
As long as Magrathea has a backup I say we go for it.
If you make a tiny black hole you start a race between evaporation and accretion. The black hole may well evaporate before it collects enough mass to be stable, but it is difficult to be completely sure about this. In theory the black hole can start from the mass of an atom and increase in mass to the mass of the Earth (plus us of course).
Yeah. I got some cheap tickets from work before Christmas. I will probably go along this week.
Thats true, and as another poster pointed out to me, the average traveller won't act like a bomber anyway.
The difference between life and games is that games has rules.
Do you live in an Anarchist society?
The IMAX in Melbourne is booked solid into next week for Avatar. I have never seen it more than 30% full in the 15 or so years it has been open.
Old story. Back in the days when dumb computer terminals were a new idea a museum had one set up so that people could play with it. Typing words, etc. Of course school groups would come through and it would get covered with rude words so some bright spark wrote a program to filter out the rude words.
Everybody was happy until a bright young geek in a school group saw the flaw in the system. The filtering program had to have a management interface with a way to display the banned list. If that interface could be found much typing could be saved and much embarrassment created...
The big flaw in the filter is that nobody can ever know what is being filtered, otherwise bypassing the filter can be made trivial and the filter will its self be a handy list of nasty stuff for people to go to. So if the filter ever becomes a political tool there will be no easy way for the public to find out. I think this flaw should be pushed as the most important problem in the system.
How is your depth perception generally? Are you okay with ball games like tennis?
Soccer I suppose.
I know those passengers were inbound to Japan at the time but its just a good thing none of them went on to Malaysia or Indonesia with the cannabis.
In 1997 in Galway, Ireland I watched the Army deliver money to a bank. They don't use security guards for that in Ireland. Or didn't, anyway. They had three guys in good positions with self loading rifles triangulated on the entrance to the bank. There were hundreds of people in the street and if they had opened up with the guns many people would have died.
Money and explosives are taken very seriously in Ireland.
Christ its Ireland we are talking about. What do they do to you in Ireland if they find explosives?
This country is going to hell, this is just the tip of the iceberg. Police planting exposives in your baggage ? (WTF ? )
Slovakia?
TFA doesn't explain why the explosives were planted. One obvious reason is to test security but in that case you would have a "wicket keeper" to catch the undetected explosives.
I recall reading about police in (I think) Japan who were doing this with drugs. Planting the stuff on people then testing their inspectors. One sample got away I believe.
I expected security tests with planted explosives to come at some point, but I assumed that they would use undercover agents to test security, not innocent bystanders. However, I'd assumed the same would have happened for something like the described drug operation in Japan. I don't see how any government could do something so reckless.
They are doing a proper double blind test. The Undercover agents would give away their special status. A lot of the work of security is watching the behaviour of the travelling public. Does this person think like a bored traveller?
I chuck mine straight in the washing machine set on hot, then the dryer. Then I give it a good going over with an iron.
I don't like your chances of suing the Slovak police in Slovakia.
TFA doesn't explain why the explosives were planted. One obvious reason is to test security but in that case you would have a "wicket keeper" to catch the undetected explosives.
I recall reading about police in (I think) Japan who were doing this with drugs. Planting the stuff on people then testing their inspectors. One sample got away I believe.
The biggest mistake we make about climate change is to think of it as a short term issue. Its not. You can't look at the climate over a year or a decade and make statements about global climate change.
So yeah it is a security issue, but on the scale of the next 50 or 100 years. I don't think it is appropriate for the CIA to work on issues over that time scale.
Having said that, the CIA apparently has remote sensing assets which can contribute to the long term picture of global climate. Using data from those assets in other domains is appropriate.
My understanding of cosmology is at best limited, but shouldn't these galaxies appear red-shifted to the extreme? They are furthest and hence should be moving the away from us at an extremely fast pace. Is the name Ultra-blue restricted to element analysis based on spectrum? I'm just confused about the blue light.
Looking at this bit:
They are so blue that they must be extremely deficient in heavy elements, thus representing a population that has nearly primordial characteristics."
I assume this means that light, hydrogen-heavy objects will get hotter for a given amount of heat energy because of their lower density. Maybe these galaxies are red shifted, but they are relatively blue in relation to their red shift.
It seems different providers in Aus just make TV available over 3G. No stress about it here.
Thats news to me. How do you access it?