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1
New Theories / Re: Post Orgasmic Illness Syndrome (POIS)
« Last post by desperate man on Today at 21:54:43 »
Just read about acetylcholine and dopamine. Thought that it should help increase dopamine all along, but they seem to have an inverse relationship. I think we can all agree on that the best neurochemical issue that matches ALL of our symptoms is elevated acetylcholine. This has been mentioned on POIS boards a few hundred times. Has anyone had success with lowering ACh? What natural methods are used for lowering it and what is the cause behind it?
2


r1 → ∞, but it could never reach infinity.
obviously, by definition. 

Quote
r2 → ∞, but it could never reach infinity.
also true, but as it is increasing more quickly than r1 it must at all times be greater than r1 and increasingly so, which means the inifinity iit is tending to must be larger than that of r1.

Quote
Your reasoning is impeccable, as long as you consider infinity as a finite distance, which, manifestly it is not.
No, it's only impeccable if you understand that there are different infinities.

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In this, and all of your examples, you are using mathematical infinities; I have no problem with that, and your arguments make perfect sense, as long as one remembers that mathematical infinities are approximations.
Not at all. The definition of any infinity is absolutely precise. Take the simplest infinity: 1/x where x→0. x=0 is an absolutely precise statement, not an approximation to anything.

As for Welsh, there must surely be an infinity of words if any letter can be considered a vowel and any consonant can be pronounced in any way as long as it doesn't sound like English.  The clever bit is that they all mean "the beautiful sadness of the oppressed". Or was my Welsh neice lying about the song she sang at the last Eisteddfodd?
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Physics, Astronomy & Cosmology / Re: Is infinity a misconception?
« Last post by Bill S on Today at 21:29:47 »
Quote from: JeffreyH
The point here is that any system that can normally be considered as bounded cannot include an infinite component.

Great!

Quote from: alancalverd
Precisely.

Terrific!!

Quote from: Pete
Let me make this very clear first; [infinity] is not a number.

It’s all coming together; but wait!  A little voice in the depths of my mathematical ignorance says:  “What about the interval from 1 to 2?  This is bounded on both sides by an integer, yet - 

Quote from: alancalverd
  Indeed there is an infinite number of rational numbers between any two integers.

Does it all depend on what we decide that “infinite” should mean?"

Take consolation from the fact that AC got the number of his verb to agree with that of the noun with which it is construed.  That’s more than most people seem to be able to manage in that sort of sentence.    ;)
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yep, seems possible Chris. A perfectly formed, evenly distributed density- spaghetti, without hidden 'faults', should then only break into two, right? At last a simple experiment )
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Physics, Astronomy & Cosmology / Re: Is infinity a misconception?
« Last post by jeffreyH on Today at 19:43:53 »
Yes my flawed logic. Apologies Pete.
6
What about using something like

AMAZING OPTICAL ILLUSIONS - HD
or
How The Chalk Guys Do It
or
Fantastic Sidewalk Art (The Chalk Guys) (this has better chalk art)
for camouflaging?
7
Physics, Astronomy & Cosmology / Re: What is quantum tunnelling?
« Last post by chiralSPO on Today at 18:54:43 »
But what about a particle tunneling?
Eh, that should mean restmass..
=

What I probably should ask is in what way (assuming that it is electrons, not only 'photons' tunneling) a vacuum barrier forbid this electron from materializing in it? Alternatively it is force carriers that tunnel here, meaning 'photons' in which case the question still stands about 'rest mass'. As a photons 'path' experimentally only exist in its sources 'recoil' and subsequent sink(measurement of it) that one meets no problems with me. A wave function makes a lot of sense there.

The "barrier" that needs to be tunneled through is just a region of space where the potential is much higher--this could be related to the pauli exclusion principle if there are occupied low energy states, requiring that a higher energy state be occupied--but there could also be no low-energy state in a particular region (vacuum is higher energy than near the positively charged nucleus of an atom). I think of tunneling as leakage of the wavefunction of an electron (or other particle) through a region that only allows for significantly higher energy states than the two regions it is between in which the particle is likely to be found. The particle does not have to be observable in the barrier region, for the particle to be observable (interactable) on both sides.
8
Technology / Re: How safe is your personal data?
« Last post by chris on Today at 18:48:44 »
Good point.

This is a nice description of how secure connections work:

http://robertheaton.com/2014/03/27/how-does-https-actually-work/
9
Physics, Astronomy & Cosmology / Re: Is the universe infinite?
« Last post by Bill S on Today at 18:36:36 »
Quote from: alancalverd
But then I live in East Anglia, and round 'ere we knows what flat looks like, boy.

Should that have been "bor", or are you too far from Norfolk for that?   :)
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Physics, Astronomy & Cosmology / Re: Is infinity a misconception?
« Last post by PmbPhy on Today at 18:32:11 »
Quote from: Bill S
If, as seems to be the case, you are saying it is impossible for two particles to be an infinite distance apart; I'm very happy with that.
Absolutely since if two particles exist then they have a finite distance between then and infinite is not a distance.
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