Den Pressure - A Definable Hypothesis & Experiments (Scepti, iWitness)

Quote from: AdamSK on August 02, 2016, 07:57:27 AM

So if we use a vacuum pump on an enclosed space, will that reduce the weight of the objects therein?

You have to weigh them and that requires man made scales which are also made under atmospheric conditions which means they can be affected by the change.

I would expect them to be affected - but by the same amount rather than proportional to the density of the objects.

Try the experiments with manual kitchen scales (not digital) in a chamber and see what results you come up with.
Don't see this as an argument against me, see it as an experiment for your own mind..

That's my attitude generally.  All of these are potential experiments to distinguish different models.

No. It's not about being easier to actually squash. It's about being able to release trapped atmosphere within the object. If you can't release the trapped atmosphere, then your object has little or none of it, meaning it's basically very dense.

Diamond isn't very dense, but it's still pretty much impossible to squash.  Is it that the atmosphere is just trapped really really well, or is there some other reason?

Quote from: sceptimatic on August 02, 2016, 08:12:09 AM

No. It's not about being easier to actually squash. It's about being able to release trapped atmosphere within the object. If you can't release the trapped atmosphere, then your object has little or none of it, meaning it's basically very dense.

Diamond isn't very dense, but it's still pretty much impossible to squash.  Is it that the atmosphere is just trapped really really well, or is there some other reason?

I'll leave that for you or anyone else to guess. I know nothing about the make up of diamonds.

I'll leave that for you or anyone else to guess. I know nothing about the make up of diamonds.

Diamonds are just a particularly obvious example.  More generally, a material's density is not the same as its compressibility - solids can be extraordinarily difficult to compress but still be lighter than other solids.
I had read your earlier statement as saying that all items of a particular density should be equally easy to squeeze, but now I see that you are not saying that.
How can we measure if a particular item has any air left in it?  I presume you don't believe in standard chemistry's description of atomic and molecular structure.

Quote from: AdamSK on August 02, 2016, 08:26:32 AM

Diamond isn't very dense, but it's still pretty much impossible to squash.  Is it that the atmosphere is just trapped really really well, or is there some other reason?

I'll leave that for you or anyone else to guess. I know nothing about the make up of diamonds.

I will take a guess -- although, it does not seem profound to me. 

The crystalline structure of diamonds permits more/less/different vibration through itself than does metal. 

Rather than thinking of air/atmospheric pressure entering dense objects, it seems like air pressure is a consequence of a dense object repelling outside vibration. 

Air inside a sponge or wood or metal is only a result of the interaction of vibrating matter. 

Quote from: sceptimatic on August 02, 2016, 08:36:19 AM

I'll leave that for you or anyone else to guess. I know nothing about the make up of diamonds.

Diamonds are just a particularly obvious example.  More generally, a material's density is not the same as its compressibility - solids can be extraordinarily difficult to compress but still be lighter than other solids.
I had read your earlier statement as saying that all items of a particular density should be equally easy to squeeze, but now I see that you are not saying that.
How can we measure if a particular item has any air left in it?  I presume you don't believe in standard chemistry's description of atomic and molecular structure.

I don't want to go into this atomic structure stuff because none of us really know what the hell it all is and neither do scientists. It's just stuff made up to try and explain things, to make them appear workable. I know, I know, we can argue about it all but let's not do it in this topic as it just becomes congested with stuff we all cannot basically answer.

Quote from: sceptimatic on August 02, 2016, 08:36:19 AM

Quote from: AdamSK on August 02, 2016, 08:26:32 AM

Diamond isn't very dense, but it's still pretty much impossible to squash.  Is it that the atmosphere is just trapped really really well, or is there some other reason?

I'll leave that for you or anyone else to guess. I know nothing about the make up of diamonds.

I will take a guess -- although, it does not seem profound to me. 

The crystalline structure of diamonds permits more/less/different vibration through itself than does metal. 

Rather than thinking of air/atmospheric pressure entering dense objects, it seems like air pressure is a consequence of a dense object repelling outside vibration. 

Air inside a sponge or wood or metal is only a result of the interaction of vibrating matter.

Well to be fair, vibrating matter plays a massive part in it all because there is no atmosphere without the vibration of matter/molecules and the frequency.

So on that note you are on the right lines.

Quote from: Charming Anarchist on August 02, 2016, 09:07:11 AM

Quote from: sceptimatic on August 02, 2016, 08:36:19 AM

Quote from: AdamSK on August 02, 2016, 08:26:32 AM

Diamond isn't very dense, but it's still pretty much impossible to squash.  Is it that the atmosphere is just trapped really really well, or is there some other reason?

I'll leave that for you or anyone else to guess. I know nothing about the make up of diamonds.

I will take a guess -- although, it does not seem profound to me. 

The crystalline structure of diamonds permits more/less/different vibration through itself than does metal. 

Rather than thinking of air/atmospheric pressure entering dense objects, it seems like air pressure is a consequence of a dense object repelling outside vibration. 

Air inside a sponge or wood or metal is only a result of the interaction of vibrating matter.

Well to be fair, vibrating matter plays a massive part in it all because there is no atmosphere without the vibration of matter/molecules and the frequency.

So on that note you are on the right lines.

Let's not discuss things we cannot observe ourselves.  Vibrating matter being one of those things.  Until we can observe it it doesn't really exist.

Actually getting chamber with low air pressure is pretty easy and obvious:
Take a syringe close the hose with wax, and, open it under water. Two things you will observe:
0) Water will not enter the syringe,
1) there will be force pushing the handle back (because there is near vacuum)

Is it KOSHER from FET point of view?

Quote from: AdamSK on August 02, 2016, 09:04:55 AM

Quote from: sceptimatic on August 02, 2016, 08:36:19 AM

I'll leave that for you or anyone else to guess. I know nothing about the make up of diamonds.

Diamonds are just a particularly obvious example.  More generally, a material's density is not the same as its compressibility - solids can be extraordinarily difficult to compress but still be lighter than other solids.
I had read your earlier statement as saying that all items of a particular density should be equally easy to squeeze, but now I see that you are not saying that.
How can we measure if a particular item has any air left in it?  I presume you don't believe in standard chemistry's description of atomic and molecular structure.

I don't want to go into this atomic structure stuff because none of us really know what the hell it all is and neither do scientists. It's just stuff made up to try and explain things, to make them appear workable. I know, I know, we can argue about it all but let's not do it in this topic as it just becomes congested with stuff we all cannot basically answer.

Lol... Or actually not. Don't say scientists know nothing. Amount other things there is  x Ray crystallography. Look up minerals and you will find known crystal structures.

Scepti, can you review experiment 2?

Going by the rule of impermeability = weight:

So you take a sponge and the same size square of concrete.  The concrete weighs more obviously.  The sponge is very porous.  Concrete is also porous but less so.  I take the sponge and soak it in silicone caulk.  It is now less porous than the concrete.  Does that mean the sponge now weighs more than the concrete?

Would that be a valid experiment?

Imagine a block of Lead and a block of wood and a sponge, all of equal size to the eye.
We know that the Lead is heavier than the wood and the wood is heavier than the sponge.

Imagine a block of Lead and a block of iron and a block of aluminum, all of equal size to the eye. 
We know that iron is heavier than aluminum and lead is heavier than iron.

The reason this is the case is because the Lead repels/resists the atmospheric pressure upon it and the ground is the solid in which the Lead pushes against, so we now perceive a push on push effect.

So you're suggesting that lead repels/resists the atmospheric pressure than iron or aluminum?  How can that be?

Quote from: sceptimatic on August 02, 2016, 07:01:13 AM

Imagine a block of Lead and a block of wood and a sponge, all of equal size to the eye.
We know that the Lead is heavier than the wood and the wood is heavier than the sponge.

Imagine a block of Lead and a block of iron and a block of aluminum, all of equal size to the eye. 
We know that iron is heavier than aluminum and lead is heavier than iron.

Quote from: sceptimatic on August 02, 2016, 07:01:13 AM

The reason this is the case is because the Lead repels/resists the atmospheric pressure upon it and the ground is the solid in which the Lead pushes against, so we now perceive a push on push effect.

So you're suggesting that lead repels/resists the atmospheric pressure than iron or aluminum?  How can that be?

It should be tested using experiment 2.

What if, for example, we placed a ball of lead on top of a sponge? That would depress the sponge, forcing air out of it (no matter which model you believe). I think everyone ought to agree that the weight of the ball on top of the sponge would be slightly less than the weight of the ball plus the weight of the sponge.

There is something to what Scepti's saying, as far as this goes. Typically it'd be thought of as density, Scepti's just saying less dense objects essentially have 'more room' for air/atmospheric pressure to get inside.
So an interesting experiment might be to be able to work out how to differentiate between the two, if that's even possible.

I do like the sound of experiment 2 though. Easily doable, and there are clear predictions. By the model of gravity, air's just been replaced with water so their differences in weight wouldn't change that much. By denpressure, if it's down to atmosphere getting into the object, that's all been removed and they'd have relatively equal volume. If it's done quickly...
Does come down to what Scepti says though. Even if there is something you didn't take into account, if nothing else it helps define denpressure in more detail.

What if, for example, we placed a ball of lead on top of a sponge? That would depress the sponge, forcing air out of it (no matter which model you believe). I think everyone ought to agree that the weight of the ball on top of the sponge would be slightly less than the weight of the ball plus the weight of the sponge.

No. There will be no difference in weight unless sponge is soaked with water and when you place a ball on it it takes water out of it.

Quote from: Jane on August 02, 2016, 12:16:24 PM

What if, for example, we placed a ball of lead on top of a sponge? That would depress the sponge, forcing air out of it (no matter which model you believe). I think everyone ought to agree that the weight of the ball on top of the sponge would be slightly less than the weight of the ball plus the weight of the sponge.

No. There will be no difference in weight unless sponge is soaked with water and when you place a ball on it it takes water out of it.

Very, very slight but I think there would be: there's always going to be air in the sponge that's weighed as well thanks to gravity (functionally a little would be caught within). Though I agree it ought to be more distinct under the denpressure model.

Actually getting chamber with low air pressure is pretty easy and obvious:
Take a syringe close the hose with wax, and, open it under water. Two things you will observe:
0) Water will not enter the syringe,
1) there will be force pushing the handle back (because there is near vacuum)

Is it KOSHER from FET point of view?

The force pushing it back is the compression of air inside the syringe, then the water, aided by the push of atmospheric pressure upon the water.
Your near vacuum thought would not produce any force on its own, it merely creates that lower pressure against the higher pressure compression that you initially pushed..

Scepti, can you review experiment 2?

Experiment 2 looks pretty good in how you want it set up.
It's clear that you're doing your homework on this.

Going by the rule of impermeability = weight:

So you take a sponge and the same size square of concrete.  The concrete weighs more obviously.  The sponge is very porous.  Concrete is also porous but less so.  I take the sponge and soak it in silicone caulk.  It is now less porous than the concrete.  Does that mean the sponge now weighs more than the concrete?

Would that be a valid experiment?

Look at experiment 2.

Imagine a block of Lead and a block of iron and a block of aluminum, all of equal size to the eye. 
We know that iron is heavier than aluminum and lead is heavier than iron.
So you're suggesting that lead repels/resists the atmospheric pressure than iron or aluminum?  How can that be?

Because the Lead, Iron and aluminium absorb different amounts of atmospheric pressure. It's trapped in some metals more than others as well as absorbed into some.
The trapped atmosphere is your magnets but we won't go into that.

What if, for example, we placed a ball of lead on top of a sponge? That would depress the sponge, forcing air out of it (no matter which model you believe). I think everyone ought to agree that the weight of the ball on top of the sponge would be slightly less than the weight of the ball plus the weight of the sponge.

There is something to what Scepti's saying, as far as this goes. Typically it'd be thought of as density, Scepti's just saying less dense objects essentially have 'more room' for air/atmospheric pressure to get inside.
So an interesting experiment might be to be able to work out how to differentiate between the two, if that's even possible.

I do like the sound of experiment 2 though. Easily doable, and there are clear predictions. By the model of gravity, air's just been replaced with water so their differences in weight wouldn't change that much. By denpressure, if it's down to atmosphere getting into the object, that's all been removed and they'd have relatively equal volume. If it's done quickly...
Does come down to what Scepti says though. Even if there is something you didn't take into account, if nothing else it helps define denpressure in more detail.

Exactly right. I like the way you think and it appears you and sandman have the grasp of it all.

Quote from: markjo on August 02, 2016, 10:58:41 AM

Imagine a block of Lead and a block of iron and a block of aluminum, all of equal size to the eye. 
We know that iron is heavier than aluminum and lead is heavier than iron.
So you're suggesting that lead repels/resists the atmospheric pressure than iron or aluminum?  How can that be?

Because the Lead, Iron and aluminium absorb different amounts of atmospheric pressure. It's trapped in some metals more than others as well as absorbed into some.
The trapped atmosphere is your magnets but we won't go into that.

Pressure is not a substance to absorb, what do you mean?  How is it measured?

Quote from: markjo on August 02, 2016, 10:58:41 AM

Imagine a block of Lead and a block of iron and a block of aluminum, all of equal size to the eye. 
We know that iron is heavier than aluminum and lead is heavier than iron.
So you're suggesting that lead repels/resists the atmospheric pressure than iron or aluminum?  How can that be?

Because the Lead, Iron and aluminium absorb different amounts of atmospheric pressure. It's trapped in some metals more than others as well as absorbed into some.
The trapped atmosphere is your magnets but we won't go into that.

Actually, metal foundries work very hard to make sure that no atmosphere is absorbed into their metals because most of the elements in the atmosphere make the metals weaker.  For example, when iron absorbs atmosphere, you get rust.

This is a (slightly edited) post I made about six months ago. It is about metals which cannot "absorb" any atmosphere. If they did any container made from these would leak air, and that does not happen.

The weight of an object simply cannot be caused by atmospheric pressure for numerous reasons. 
Here are a few:

• Air pressure presses almost equally all around an object, so causes no nett downward force.  In fact, the pressure is (very) slightly higher at the bottom than the top, so there is slight buoyancy (Archimedes principle)
  
• The weight of an object actually increases very slightly in a very low pressure chamber (loosely called a "vacuum chamber") due to the loss of the  buoyancy mentioned in (1)
  
• If the weight of an object was due to atmospheric pressure the weight would be higher for an object of the same mass but larger volume, in fact, the opposite is true (though the difference is very slight unless the volume is very large - eg a helium balloon).

Another example.  Suppose we have 4 identical cube shaped blocks of 10 cm each side made of 4 different metals.  The following table gives the mass (and weight) in kilograms:

Magnesium		1.80 kg
Steel		7.85 kg
Lead		11.37 kg
Gold		19.36 kg

Now these blocks have exactly the same shape and size, yet have very different masses and weights.
How could this be if the weight was due to atmospheric pressure?

No-one is going to convince me, without experimental evidence, that any of these metals can absorb a measureable amount of atmosphere.

Quote from: sceptimatic on August 02, 2016, 02:35:53 PM

Quote from: markjo on August 02, 2016, 10:58:41 AM

Imagine a block of Lead and a block of iron and a block of aluminum, all of equal size to the eye. 
We know that iron is heavier than aluminum and lead is heavier than iron.
So you're suggesting that lead repels/resists the atmospheric pressure than iron or aluminum?  How can that be?

Because the Lead, Iron and aluminium absorb different amounts of atmospheric pressure. It's trapped in some metals more than others as well as absorbed into some.
The trapped atmosphere is your magnets but we won't go into that.

Actually, metal foundries work very hard to make sure that no atmosphere is absorbed into their metals because most of the elements in the atmosphere make the metals weaker.  For example, when iron absorbs atmosphere, you get rust.

That depends on the metals.
You cannot keep out atmospheric pressure from probably any metals but you can go a long way into minimizing it; especially in soft metals like Lead and gold, etc.
You see, these metals are under or have been under severe pressure underground in liquid form. When forced up they become a solid but a soft solid due to their make up.

Up top, or closer, we have the metals we regularly use and we have to use a lot of energy to get the metals from the ground by friction or in basic terms, melting it out by furnace which makes it extremely expanded. From this point on it depends how it's cooled and how much pressure is applied during cooling, plus how many re-heats it gains. Etc etc.
Basically metals become more or less porous depending on how and where they were mined and by what means they were extracted to form what we know as the metals we see and use.
The list is long and complicated to actually go through so I'm sure you get my meaning.

Good point from Markjo: what causes rust?
Typically it'd be contact with the air, which causes it on the outside surface. If air's within a metal too, shouldn't we observe it just as much on the inside? Or do you accept another cause?

Quote from: markjo on August 02, 2016, 03:34:06 PM

Quote from: sceptimatic on August 02, 2016, 02:35:53 PM

Quote from: markjo on August 02, 2016, 10:58:41 AM

Imagine a block of Lead and a block of iron and a block of aluminum, all of equal size to the eye. 
We know that iron is heavier than aluminum and lead is heavier than iron.
So you're suggesting that lead repels/resists the atmospheric pressure than iron or aluminum?  How can that be?

Because the Lead, Iron and aluminium absorb different amounts of atmospheric pressure. It's trapped in some metals more than others as well as absorbed into some.
The trapped atmosphere is your magnets but we won't go into that.

Actually, metal foundries work very hard to make sure that no atmosphere is absorbed into their metals because most of the elements in the atmosphere make the metals weaker.  For example, when iron absorbs atmosphere, you get rust.

That depends on the metals.
You cannot keep out atmospheric pressure from probably any metals but you can go a long way into minimizing it; especially in soft metals like Lead and gold, etc.
You see, these metals are under or have been under severe pressure underground in liquid form. When forced up they become a solid but a soft solid due to their make up.

Up top, or closer, we have the metals we regularly use and we have to use a lot of energy to get the metals from the ground by friction or in basic terms, melting it out by furnace which makes it extremely expanded. From this point on it depends how it's cooled and how much pressure is applied during cooling, plus how many re-heats it gains. Etc etc.
Basically metals become more or less porous depending on how and where they were mined and by what means they were extracted to form what we know as the metals we see and use.
The list is long and complicated to actually go through so I'm sure you get my meaning.

Scepti, I'm not exactly sure what you're talking about here. Take steel pipez on a pipeline. The materials running through the pipeline are at 1000's of lbs. psi. How pourous can the steel in the pipeline be?  I don't think there can be any air or any gas in the steel.

Quote from: neutrino on August 02, 2016, 09:49:34 AM

Actually getting chamber with low air pressure is pretty easy and obvious:
Take a syringe close the hose with wax, and, open it under water. Two things you will observe:
0) Water will not enter the syringe,
1) there will be force pushing the handle back (because there is near vacuum)

Is it KOSHER from FET point of view?

The force pushing it back is the compression of air inside the syringe, then the water, aided by the push of atmospheric pressure upon the water.
Your near vacuum thought would not produce any force on its own, it merely creates that lower pressure against the higher pressure compression that you initially pushed..

Whatever. Do you accept that you'll get a cavity with tremendously lower atmospheric pressure? Like 1 tenth of what we have? Will then same object weigh less in this cavity?

Nice to see scepti back and in full flow.   

I would have titled the thread  Denspressure,   Den Pressure sounds like something to do with the social hierarchy of foxes.