Ask a physicist anything. (5)

[Wiccan_Child]

Why would you need to change the law (conservation of energy and momentum) when it seems it can simply be ignored?

Because conservation laws have been shown to be necessary in any symmetric model of reality (electrons/positrons, etc). As I said initially, conservation laws aren't being ignored - energy and momentum are the same before as they are after.

 

[TheReasoner]

Why would you need to change the law (conservation of energy and momentum) when it seems it can simply be ignored?

Nono. It's conserved alright.
I'm sure WC can explain better than I can. But as I understand it, and I haven't had a course on this subject - just FYI, this is all me studying on my own - you can easily have particles be generated from nothing so long as you have a negative opposite be created at the same time. You will then get conservation of mass because you add both a positive and an equal but negative amount of matter to the universe, hence not altering the balance a whit.

Consider the following. You go to your friend and borrow a hundred dollars. Have you become a hundred dollars richer? No. You have one hundred dollars in cash and the same amount in debt. You have neither gained nor lost anything. The same is the case when virtual particles show up.

Is that a decent if rather boiled down explanation WC?

 

[1611AV]

Is the core of the Earth hotter than the surface of the sun? Also, How do we measure the temp of earths core?

 

[Wiccan_Child]

Is the core of the Earth hotter than the surface of the sun? Also, How do we measure the temp of earths core?

The surface of the Sun is ~6000K, while the atmosphere above it (the corona) can be upwards of 2 million K. The Earth's core is about 5700K.

So the Earth's inner core is about as hot as the surface of the Sun (its atmosphere notwithstanding).

We measure the temperature of the core using Earthquakes - the time it takes earthquakes to propagate through the Earth, as well as how and when and how strongly earthquakes are reflected off various materials, can all be used to deduce the inner structure of the Earth, including its temperature.

 

[1611AV]

What is everything made of ?

 

[1611AV]

If the Moon is billions of years old, or more, why is there so little depth of moon dust on its surface?

 

[Doveaman]

The surface of the Sun is ~6000K, while the atmosphere above it (the corona) can be upwards of 2 million K.

How is the atmosphere above the surface of the sun so much hotter than the surface if the heat is generated at the core?

Shouldn't it get cooler as the heat rises from the core, and not hotter?

And if the heat is generated at the core why are sunspots so dark and cooler than the surface?

 

[Blayz]

What is everything made of ?

Can't speak for everything, but it is my understanding that girls are made of sugar and spice, and everything nice, whereas boys seem to be an admixture of various amphibian, mollusc and mammalian body parts.

 

[freezerman2000]

I don't have time to go through the entire forum, but how do you see the universe forming? As a layman, I don't understand equations , so please keep it simple....TY

 

[mandyangel]

Hey I'm curious for the physicist... do you think offshore drilling is a good idea? if there would be some minor harm to whatever in doing it, is it being overstated? also what do you think about global warming? And the increasing heat of magma rock?

Thanks in advance, mandy

 

[freezerman2000]

If the Earth is always changing, is it evolving?...If it is could that be an argument for evolution in living beings over long periods of time?
If God made the earth and it is changing, why not living beings?

 

[mzungu]

Hey I'm curious for the physicist... do you think offshore drilling is a good idea? if there would be some minor harm to whatever in doing it, is it being overstated?

Ofshore oil drilling does pose serious risks. However if the technology exists that can address a leak very quickly then the impact of such a leak will be small. But at present as the BP disaster showed; We do not have the capability to plug deep water leaks quickly and the resulting pollution causes massive ecological damage.

also what do you think about global warming? And the increasing heat of magma rock?

Global warming has nothing to do with magma unless a supervolcano eruption takes place. On the other hand volcanic eruptions end up dropping the global temperature. Also magma temperatures are not increasing and in fact the earth as a body will eventually cool into a solid and thus loose its magnetic field and result in the loss of our atmosphere due to solar wind activity.

 

[mandyangel]

Ofshore oil drilling does pose serious risks. However if the technology exists that can address a leak very quickly then the impact of such a leak will be small. But at present as the BP disaster showed; We do not have the capability to plug deep water leaks quickly and the resulting pollution causes massive ecological damage.
Global warming has nothing to do with magma unless a supervolcano eruption takes place. On the other hand volcanic eruptions end up dropping the global temperature. Also magma temperatures are not increasing and in fact the earth as a body will eventually cool into a solid and thus loose its magnetic field and result in the loss of our atmosphere due to solar wind activity.

disagree on the oil but thanks 4 the reply!

 

[TheReasoner]

Hey I'm curious for the physicist... do you think offshore drilling is a good idea? if there would be some minor harm to whatever in doing it, is it being overstated? also what do you think about global warming? And the increasing heat of magma rock?

Thanks in advance, mandy

Increasing heat of the magma? I'm no geologist, but where would the energy to heat it come from? You can't have something simply heating up without a cause. You need to have something doing the heating. As for the atmosphere the heating agent is simple to identify: The sun is constantly pumping it's radiation (visible light etc) in our direction. Several pollutants we make can absorb and hold onto this heat by a number of methods. But the magma?

Offshore drilling risk assessment is something i'll refrain from doing lightly. But I'll say that I am opposed to it unless significant safety measures are enforced. Strictly. The potential damage of an accident is extreme and far reaching. As a nanotechnologist I feel I should advocate my own field and say that we should increase funding to research into radial solar cells, batteries and various other methods of energy harvesting and storing. Osmotic power for example.

Nanotech for the win! ^^

 

[1611AV]

Can't speak for everything, but it is my understanding that girls are made of sugar and spice, and everything nice

After much observation of the female human species, I would have to conclude this statement to be very false. Except for my wife of course

 

[mzungu]

disagree on the oil but thanks 4 the reply!

You are welcome. As for the oil thing; Well let me put it this way: Deep water oil drilling at the present damage control technology level is like a fighter jet without an ejection seat!

There is no reason why we cannot do deep water drilling so long as we have the technology to arrest a leak should it happen before the oil causes ecological and commercial damage.

There is absolutely no doubt as to the damage crude oil spills cause on the ecology of the sea and shore!

 

[1611AV]

According to the ToE. When life first emerged on earth, was there Male and Female? Or did that evolve as well? Thanks

 

[mzungu]

According to the ToE. When life first emerged on earth, was there Male and Female? Or did that evolve as well? Thanks

ToE does not indulge in HOW LIFE BEGAN. All it does is show how life evolved after it began. Your question should be aimed at Abiogenesis and not ToE.

Many primiti8ve life forms exhibit Asexual reproduction. That's nothing new!

 

[1611AV]

ToE does not indulge in HOW LIFE BEGAN. All it does is show how life evolved after it began. Your question should be aimed at Abiogenesis and not ToE.

Many primiti8ve life forms exhibit Asexual reproduction. That's nothing new!

Let me re address... According to science, were the first living things male and female?

 

[chris4243]

Let me re address... According to science, were the first living things male and female?

We don't even know what the first living things were. But there is good reason to assume they were asexual reproducers, because that is far simpler and safer. Even now, most reproduction including yourself is done asexually (your trillion or so cells, not the egg+sperm they're derived from).