Ask a physicist anything. (6)

[Cactus Jack]

Exactly what is entailed in becoming a physicist?
c

 

[Wiccan_Child]

Exactly what is entailed in becoming a physicist?
c

Formal training and qualification in either physics in general or some specialisation thereof.

 

[mzungu]

Do you think dad has a brother?

 

[Chalnoth]

Exactly what is entailed in becoming a physicist?
c

Well, nearly all physicists gain their training by first obtaining a bachelor's of science in physics, and then going on to graduate school in physics.

But as for what physicists do in coursework, well, I don't know your background so I'll use the most basic explanation I can think of. If you remember the word problems you've seen in math class, well, physics is nothing but that kind of problem. The problems get more challenging, but they also become more sensible. That is, they aren't quite as arbitrary or ad-hoc as the word problems you get in high school and previous, in that the problems often give real insight into the way the world works.

But, for the most part, that kind of problem is what physics education is all about. To do well in physics, you have to learn to both think logically and be able to do algebra and calculus quite well.

 

[razeontherock]

So sayeth one who knows nothing about the meaning of the word "Empirical".

Please answer the following questions:
How old are you.
How tall are you.
How much do you weigh.

You are not allowed to use any empirical measurements nor empirical means to answer the question lest you be in violation of your anti empirical claims.

 

[oriel36]

Exactly what is entailed in becoming a physicist?
c

A physicist/empiricist believes there is no distinction between the behavior of objects at a human level and the motions of the planets as it is ingrained in their doctrine which is more or less derived from Newton Such a hold has that Arian heretic on his followers that anything he says goes no matter how ridiculous and that genuine Christians are being obstructed from appreciating astronomy by doctrines which are utterly stupid reflects more on us as Christians than the cult followers.An example follows.

If you look out at the moon,you will see it orbiting the Earth as the variations in light and shadow or 'phases' denote its orbital position around the Earth where sometimes it is between the Earth and the Sun ( New moon) and sometimes the opposite side where the Earth is between the moon and the Sun (Full moon).Now we see the same face of the moon constantly and would normally conclude that the moon has no rotation but Isaac Newton,and only Isaac ,decided that the moon rotates so his physicist followers to this day will go to great lengths to explain how the moon rotates thereby defying common sense.

In short,astronomy is an interpretative endeavor rather than a speculative one yet physicists are concerned with 'predictions' owing to the way they organize things to suit their perspective.They become the new prophets with their empirical laws hence the erosion of prophesy as Christians once knew the term as it applies to wisdom/intepretation but the physicist's view is a bell with a crack in it.The damage done in the late 17th century which allowed the 'predictive' agendas to emerge was the attempt to model planetary dynamics using the calendar system and clocks whereas today the damage done by computer 'modelling' and is creating an even worse 'predictive' mess by virtue of the same type of shortcuts applied by Newton and his contemporaries are seen today in areas such as climate.

People seemingly do have a need to look to scientists as being honest and to be fair to contemporary physicists they are merely imitating those who came before them and do not intentionally go out to cause havoc but when the issues get serious as they are at present,any empathy for genuine physicists has to be set aside as all have to learn from scratch.

 

[mzungu]

A physicist/empiricist believes there is no distinction between the behavior of objects at a human level and the motions of the planets as it is ingrained in their doctrine which is more or less derived from Newton Such a hold has that Arian heretic on his followers that anything he says goes no matter how ridiculous and that genuine Christians are being obstructed from appreciating astronomy by doctrines which are utterly stupid reflects more on us as Christians than the cult followers.An example follows.

If you look out at the moon,you will see it orbiting the Earth as the variations in light and shadow or 'phases' denote its orbital position around the Earth where sometimes it is between the Earth and the Sun ( New moon) and sometimes the opposite side where the Earth is between the moon and the Sun (Full moon).Now we see the same face of the moon constantly and would normally conclude that the moon has no rotation but Isaac Newton,and only Isaac ,decided that the moon rotates so his physicist followers to this day will go to great lengths to explain how the moon rotates thereby defying common sense.

In short,astronomy is an interpretative endeavor rather than a speculative one yet physicists are concerned with 'predictions' owing to the way they organize things to suit their perspective.They become the new prophets with their empirical laws hence the erosion of prophesy as Christians once knew the term as it applies to wisdom/intepretation but the physicist's view is a bell with a crack in it.The damage done in the late 17th century which allowed the 'predictive' agendas to emerge was the attempt to model planetary dynamics using the calendar system and clocks whereas today the damage done by computer 'modelling' and is creating an even worse 'predictive' mess by virtue of the same type of shortcuts applied by Newton and his contemporaries are seen today in areas such as climate.

People seemingly do have a need to look to scientists as being honest and to be fair to contemporary physicists they are merely imitating those who came before them and do not intentionally go out to cause havoc but when the issues get serious as they are at present,any empathy for genuine physicists has to be set aside as all have to learn from scratch.

You have just betrayed you total lack of knowledge in all matters concerning astronomy and science in general. You do not even know the difference between "ORBIT" and "rotation".

It is clear that you are here only to insult and not to debate.

I shall of now put you on my ignore list!

 

[Steffenfield]

What would the smallest, observable, nuclear explosion, like a bomb, that one could make in theory?

 

[Chalnoth]

What would the smallest, observable, nuclear explosion, like a bomb, that one could make in theory?

Well, that depends a bit upon what you mean.

I mean, it is very possible to fuse two hydrogen atoms together to make a helium atom, and observe the results. Doing this sort of thing is how we know about the details of nuclear fusion.

But if you mean, what is the smallest sustainable nuclear explosion, that's a rather different question. You can't create a sustainable nuclear explosion using fusion without it being in a star: fusion just tends to blow the fuel away so fast that the only way we are able to make thermonuclear warheads at all is to use a fission-based explosion to contain the fuel for the split second it takes much of the hydrogen to fuse.

If you mean a fission-based sustainable nuclear explosion, then what you need to generate the explosion is a runaway nuclear reaction, and that actually requires a minimum amount of fuel. Basically, the way a fission reaction works is that the nuclear fuel itself is radioactive, so that atoms within the material are periodically belting out energetic particles. These energetic particles, if they smack into a nearby atomic nucleus, can cause that nucleus to break apart, releasing more energetic particles.

If you want an explosion, you need enough of the nuclear fuel around that enough of the products of the broken-apart nuclei smack into other broken-apart nuclei that the reaction accelerates exponentially. For instance, if your block of fuel is too small, most of the products will just escape the block of fuel and not cause secondary reactions. So there's a minimum amount of fuel that you need that depends upon the shape of the block of fuel what sort of nuclear fuel it is. I don't know for certain what the absolute minimum is, but I believe I heard it was of the order of a couple hundred pounds of fuel.

Edit: Looks like Wiccan_Child found an example of a smaller device, of the order of 50lbs. It's probably going to be really, really hard to make anything smaller than that.

 

[Wiccan_Child]

What would the smallest, observable, nuclear explosion, like a bomb, that one could make in theory?

Hmm. The fission of a single atom is, technically, an explosion, so there's no lower limit. Scaling it up to observable sizes means that it would have to be about a millimetre across.

There has been a lot of work done shrinking nuclear weaponry, as it gives that country a distinct technical advantage. The smallest to date is the W54, which could fit in a large backpack.

 

[mzungu]

What would the smallest, observable, nuclear explosion, like a bomb, that one could make in theory?

Are you referring to a nuclear fision event or a nuclear bomb?

 

[Steffenfield]

Like a mini nuclear bomb.

 

[Steffenfield]

I guess what I'm asking is if it might be possible to have something like a nuclear grenade in which the splash damage when detonated was only like a radius of 20 feet or so.

Cheers!

 

[Chalnoth]

I guess what I'm asking is if it might be possible to have something like a nuclear grenade in which the splash damage when detonated was only like a radius of 20 feet or so.

Cheers!

Doesn't look like it It looks like the smallest blast you can get is of the order of a few times the Oklahoma City bombing.

 

[Steffenfield]

Now that I think about it, a nuclear grenade isn't such an awesome idea to me anymore...

Especially when you consider that I would only be able to chuck it around 19 feet.

 

[pgp_protector]

Now that I think about it, a nuclear grenade isn't such an awesome idea to me anymore...

Especially when you consider that I would only be able to chuck it around 19 feet.

Rocket Launched Nuclear grenade like Starship Troopers

 

[mzungu]

And Man said "Let there be Terminator"

BBC News - IBM produces first 'brain chips'

 

[Eudaimonist]

And Man said "Let there be Terminator"

BBC News - IBM produces first 'brain chips'

I, for one, welcome our robot overlords.


eudaimonia,

Mark

 

[mzungu]

I, for one, welcome our robot overlords.


eudaimonia,

Mark

I welcome them not as overlords but as minions!

 

[Chalnoth]

And Man said "Let there be Terminator"

BBC News - IBM produces first 'brain chips'

Somehow I doubt this is anything dramatically different from the already reasonably well-established field of FPGA computing.

FPGA = field programmable gate array. FPGA's can be dynamically reconfigured on the fly.