Search found 144 matches

by The Geoff
Tue Jun 03, 2014 10:40 am UTC
Forum: Science
Topic: Possibly illegal but ostensibly feasible money-making scheme
Replies: 17
Views: 4075

Re: Possibly illegal but ostensibly feasible money-making sc

A lot of our power in Scotland comes from hydro-storage schemes. When there's plenty of electricity to go round water is pumped up into a large reservoir, then at peak demand times it's allowed to run back down through turbines to generate power. Pre-widespread renewables it was simply used to iron ...
by The Geoff
Mon Apr 21, 2014 11:24 am UTC
Forum: Science
Topic: Return of the LHC
Replies: 7
Views: 2129

Re: Return of the LHC

new particles (which defy the known laws of physics) have been discovered! We don't really have "known laws of physics" in this context. There's lots of variants on a general theme, and some results may discount some of them - eg if we discover supersymmetric particles it wipes out a whol...
by The Geoff
Tue Apr 15, 2014 7:58 pm UTC
Forum: Science
Topic: 1338 changed my life! (veganism)
Replies: 153
Views: 22308

Re: 1338 changed my life! (veganism)

Hunter-gatherer diets today have a huge variation. The inuit get > 90% of their calories from meat and fish, the !kung get < 15% of their calories from meat and fish. The joys of being omnivorous- a wide variety of diets can provide what we need. This is, to me at least, one of the most important p...
by The Geoff
Fri Apr 11, 2014 2:42 pm UTC
Forum: Science
Topic: 1338 changed my life! (veganism)
Replies: 153
Views: 22308

Re: 1338 changed my life! (veganism)

As so often, people are making the mistake of linking a general lifestyle with the food we eat. If all 7Bn people on the planet switch to a vegan diet, AND stop driving cars, AND make buying decisions which drive mass-transit trade out of business AND only buy local foods AND only have one child per...
by The Geoff
Fri Mar 28, 2014 1:02 pm UTC
Forum: Science
Topic: Present for a Chemistry Student
Replies: 10
Views: 3028

Re: Present for a Chemistry Student

Do they have any interest in making beer or wine? I'm thinking a cheap refractometer, a little hand-held device for measuring the sugar content of a pre-brewing solution. You can get them for about £50 (~$70?). Or that oldest of chemistry gags, the dihydrogen monoxide storage solution: http://www.ca...
by The Geoff
Thu Jan 16, 2014 6:10 pm UTC
Forum: Science
Topic: Emotional Prophylactic?
Replies: 5
Views: 2709

Re: Emotional Prophylactic?

One area of research in the UK is using Ecstacy (pure MDMA rather than the street form) in PTSD treatment. The theory is that it dissociates the memory from the emotional response, so you can talk through the events causing the PTSD without the high levels of stress that you normally associate with ...
by The Geoff
Sun Jan 05, 2014 8:31 pm UTC
Forum: News & Articles
Topic: British gov. wants all sex websites blocked by default
Replies: 54
Views: 13253

Re: British gov. wants all sex websites blocked by default

From a BT customer in the UK: I've seen no filter whatsoever. I believe this is being rolled out to new customers only (and only with the 4 biggest ISPs), with it becoming available to people like me at a later date. Whether "available" means opt-in (fine) or opt-out (which I think would b...
by The Geoff
Wed Nov 27, 2013 10:28 pm UTC
Forum: Science
Topic: 3D visual perception
Replies: 40
Views: 6955

Re: 3D visual perception

There's no way to tell if an individual photon was or wasn't redshifted along the way; you have to be able to look at a spectrum and see known peaks (absorption and emission and whatnot) have shifted up and down from where they are supposed to be. And redshift only carries information about speed, ...
by The Geoff
Wed Nov 27, 2013 10:00 pm UTC
Forum: Science
Topic: 3D visual perception
Replies: 40
Views: 6955

Re: 3D visual perception

The rotation is there simply to aid with the visualisation. That gif is isn't actually a tesseract/hypercube, it's roughly what the 3D shadow of a 4D object could look like. Just as (if seen from the right angle) the shadow of a cube looks like a square - introducing rotation lets you see there's ac...
by The Geoff
Mon Nov 25, 2013 1:36 pm UTC
Forum: News & Articles
Topic: Couple Found Guilty of Murder, followed parenting book
Replies: 219
Views: 28927

Re: Couple Found Guilty of Murder, followed parenting book

How would you feel about a book called "Steal This Book" or "The Anarchists Cookbook"? Or "Mein Kampf"? All three are available and legal. The first two are explosives cookbooks, among other things, and I guess you know what the last is. At least in the US the preferen...
by The Geoff
Tue Nov 12, 2013 2:36 pm UTC
Forum: Science
Topic: Magnitude of celestial body bright enough to cast shadow
Replies: 12
Views: 5524

Re: Magnitude of celestial body bright enough to cast shadow

If I look up at, say, Rigel and then put my hand in front of my eyes I can no longer see the star. Does that not imply that I can't see it because I'm in the shadow my hand is creating? A shadow is simply photons being blocked from whatever the shadow is being cast on at the end of the day. If you c...
by The Geoff
Fri Oct 25, 2013 11:36 pm UTC
Forum: Science
Topic: Why do we perceive a 4-dimensional universe as 3?
Replies: 98
Views: 15475

Re: Why do we perceive a 4-dimensional universe as 3?

Young's Double Slit is the big "WTF" experiment for me. Then you get into the wacky delayed erasure stuff. As far as intuition goes, would it be fair to say we know the approximate initial state of a photon and the final state when it hits the screen, and there is no "in between"...
by The Geoff
Sun Sep 01, 2013 1:15 pm UTC
Forum: Science
Topic: Pound v. Foot Pound
Replies: 101
Views: 24053

Re: Pound v. Foot Pound

gmalivuk wrote:The Joule *is* a Newton-meter.


Pascal, surely? [EDIT]Sorry, ignore that, N.m vs N/m^2[/EDIT]
by The Geoff
Wed Aug 28, 2013 3:30 pm UTC
Forum: Science
Topic: Singularities and gravity
Replies: 39
Views: 11224

Re: Singularities and gravity

Does this mean an orbit inside the event horizon is impossible? Short of invoking faster than light particles or some sort of warp drive, yes. One way of defining the event horizon is as the locations in space (usually spherical-ish) where the minimum velocity to stop you falling further in is c. N...
by The Geoff
Wed Aug 28, 2013 2:56 pm UTC
Forum: Science
Topic: Dark matter & black holes
Replies: 34
Views: 10311

Re: Dark matter & black holes

I assume that any dark matter crossing an event horizon is going to behave just as normal matter? So for this particular case slowing the relative velocity via interactions isn't needed, it's going to be incorporated into the black hole regardless?
by The Geoff
Mon Aug 26, 2013 6:25 pm UTC
Forum: Science
Topic: Question about determining coefficient of friction.
Replies: 15
Views: 6409

Re: Question about determining coefficient of friction.

Interesting link, thanks. I mentioned arm strength in particular because there are situations where this is the defining reason for "failure", if you've got a crimpy little hold that you can only get the first joint of a couple of fingers onto then you'll fall off because your strength goe...
by The Geoff
Mon Aug 26, 2013 5:41 pm UTC
Forum: Science
Topic: Electric guns
Replies: 30
Views: 8309

Re: Electric guns

I'm 99% certain The Geoff was being sarcastic. He just skipped a step: What would be even more awesome is if, instead of using capacitors, you could use chemical energy as the storage for greater density, but instead of a battery, like, find some sort of (spitballing here, but humour me) flammable ...
by The Geoff
Sun Aug 25, 2013 1:01 am UTC
Forum: Mathematics
Topic: Throwing a random die
Replies: 20
Views: 4965

Re: Throwing a random die

I really need some context on this - I get the impression the OP is asking something along the lines of: "If you had a laser scanner and a fast computer could you predict the fall of dice as they are thrown?" To which, I'd guess, the answer is "certainly enough to make money before go...
by The Geoff
Sun Aug 25, 2013 12:45 am UTC
Forum: Science
Topic: Question about determining coefficient of friction.
Replies: 15
Views: 6409

Re: Question about determining coefficient of friction.

The problem with rock climbing is the huge number of different things going on. It's fairly simple to measure the coefficiant of friction of a human palm or fingertips, but you've got all the various forces between the area of the fingers/hands covering the rock, the type of rock, the angles of your...
by The Geoff
Fri Aug 23, 2013 3:47 pm UTC
Forum: Science
Topic: Dark matter & black holes
Replies: 34
Views: 10311

Re: Dark matter & black holes

If DM interacts with itself only through gravity, it will not collapse easily. Particles would fall toward the center of mass, pass through it and then fly away, oscillating around it. You need something akin to friction to slow them down close to the centre and accumulate mass. Gravitational waves...
by The Geoff
Thu Aug 22, 2013 11:36 pm UTC
Forum: Science
Topic: Electric guns
Replies: 30
Views: 8309

Re: Electric guns

As noted, it's all about energy densities, it's dumping enough energy at once that is the problem. Forget batteries, what you want is some sort of super-capacitor array. What would be super-cool, would be producing some sort of fine, powdered supercapacitor that could be stored along with the slug (...
by The Geoff
Thu Aug 22, 2013 10:06 pm UTC
Forum: Science
Topic: Dark matter & black holes
Replies: 34
Views: 10311

Re: Dark matter & black holes

We need the extremes of big stars to produce black holes specifically because there are other forces (electromagnetism, exclusion principle, degeneracy pressure etc) which prevent gravitational collapse. If (and admittedly it's a big if) DM only interacts gravitationally, even with itself, what's to...
by The Geoff
Thu Aug 22, 2013 4:40 pm UTC
Forum: Science
Topic: Dark matter & black holes
Replies: 34
Views: 10311

Re: Dark matter & black holes

Does electromagnetism have any great net effect on large clouds of gravitationally bound matter? If anything, I would have thought it prevents black hole formation, eg by "holding stars up"?
by The Geoff
Thu Aug 22, 2013 4:25 pm UTC
Forum: Science
Topic: Are ‘Evidence-based’ policies damaging policymaking?
Replies: 16
Views: 6819

Re: Are ‘Evidence-based’ policies damaging policymaking?

The problem is that politicians will use real, strong evidence if it agrees with their party line. They will also use weak or circumstantial evidence if it supports their party line. If there is evidence, strong or weak, which contradicts the party line then it will be thrown out. People the UK gove...
by The Geoff
Thu Aug 22, 2013 3:43 pm UTC
Forum: Science
Topic: Dark matter & black holes
Replies: 34
Views: 10311

Dark matter & black holes

I realise that by invoking "dark matter" everything below is very hand-wavey ;) But let's assume that DM is the standard "matter which only interacts with 'normal matter' via gravity" - does this mean that DM can form a black hole, and that this black hole would be indistinguisha...
by The Geoff
Tue Aug 13, 2013 12:29 am UTC
Forum: Science
Topic: Moon falling
Replies: 19
Views: 7576

Re: Moon falling

Even taking the lack of air into account, it seems wrong. How would the object manage to go faster than the Moon's escape velocity, despite coming from relatively close up? My guess would be that he considered both Earth's and Moon's potentional energy while on the Lagrange Point, but only the Moon...
by The Geoff
Sun Aug 11, 2013 12:26 pm UTC
Forum: Science
Topic: Moon falling
Replies: 19
Views: 7576

Re: Moon falling

With reference to the "edge of the moon's gravity", traditional physics suggests there isn't one, but I'm guessing that the accelerating expansion of spacetime means there's a "horizon" where a dropped object would never hit the surface even as time tends toward infinity? Or am I...
by The Geoff
Sun Aug 11, 2013 2:48 am UTC
Forum: Science
Topic: Moon falling
Replies: 19
Views: 7576

Re: Moon falling

In that case, the back of my envelope suggests you'd hit at 4,000mps, or about 9,000mph. That's crater material.
by The Geoff
Sat Aug 10, 2013 1:32 pm UTC
Forum: Science
Topic: Moon falling
Replies: 19
Views: 7576

Re: Moon falling

For "edge" I'd suggest the Lagrange (L1) point where the Earth's gravity balances the Moon's, so you can sit there without falling towards either (well, ignoring the fact that it's unstable equilibrium) - from there you just need a nudge towards the moon and you'll "fall" the res...
by The Geoff
Tue Jul 30, 2013 11:30 am UTC
Forum: Science
Topic: Runner on a Treadmill
Replies: 46
Views: 14146

Re: Runner on a Treadmill

Simple solution: rig up a fan to give him a tailwind equal to his velocity.
by The Geoff
Mon Jul 29, 2013 1:21 am UTC
Forum: Science
Topic: Homeopathy and Placebo Effectiveness
Replies: 14
Views: 7433

Re: Homeopathy and Placebo Effectiveness

Really? I can't think of any form in the UK that does that, it wouldn't be profitable (which is what it's all about) as it would have to go through far stricter controls as a herbal medicine. It relies on not having any effect to get it past medical red tape, but oh so quietly. One company has been ...
by The Geoff
Fri Jul 19, 2013 2:26 pm UTC
Forum: Science
Topic: Stars and Inmortality
Replies: 11
Views: 5439

Re: Stars and Inmortality

I don't see it like that - personally, I'd prefer to be forgotten unless I've done something particularly spectacular for future humans. And, of course, a few people who are guaranteed "immortality" are Hitler, Stalin and Pol Pot, I'm not sure we need to give genocidal dictators any more e...
by The Geoff
Fri Jul 19, 2013 12:55 pm UTC
Forum: Science
Topic: Stars and Inmortality
Replies: 11
Views: 5439

Re: Stars and Inmortality

Why not just name all future children after the stars? Same effect, much less paperwork, as I plan on explaining to little Wolf359.

Seriously - just because there's a star named after you you become "immortal"? Don't get that myself.
by The Geoff
Mon Jul 15, 2013 10:12 pm UTC
Forum: Science
Topic: Redneck Whale Fishing
Replies: 4
Views: 4625

Re: Redneck Whale Fishing

Operation Joint Warrior takes place round these parts, a big inter-forces training exercise including plenty of active sonar use, and it (anecdotal "data") does seem to result in a large percentage of whale and dolphin beachings. Conversely, there's a large bombing range used for cannon an...
by The Geoff
Mon Jul 15, 2013 3:06 pm UTC
Forum: Science
Topic: Multiverse broken by 4chan?
Replies: 8
Views: 4023

Re: Multiverse broken by 4chan?

Allowing fractions, there are an infinite number of numbers between 1 and 2. None of these is 3. This does not mean that 3 doesn't exist. In an analogue amplifier there are (in theory) an infinite number of settings between 3 and 4. This does not mean you can't turn it up to 10 (or even 11 if you're...
by The Geoff
Thu Jul 11, 2013 10:18 pm UTC
Forum: Science
Topic: Homeopathy and Placebo Effectiveness
Replies: 14
Views: 7433

Re: Homeopathy and Placebo Effectiveness

A placebo doesn't have to be inert - cause a few side effects and the patient will be even more convinced it's "working". This was pretty much how medicine has worked through human history, many medications were purgatives of some description, and just about the only thing that Hahnermann ...
by The Geoff
Tue Jun 25, 2013 6:20 pm UTC
Forum: Science
Topic: Quantum Computing Uses
Replies: 11
Views: 4684

Re: Quantum Mechanics Uses

Even for other sorts of problems, you can keep repeating it until you're 99.999...9% (arbitrary but finite number of 9's) certain of the result, which with enough 9's is probably comparable to a classical algorithm which gives a 'certain' result. I recall reading somewhere [citation needed] that Sh...
by The Geoff
Thu Jun 20, 2013 12:47 am UTC
Forum: Science
Topic: Conservation of information
Replies: 13
Views: 5087

Re: Conservation of information

So if information is gradually lost, the Big Bang singularity (or stringy bounce moment or whatever you prefer) would logically be the universe's moment of maximum information content? That seems counter-intuitive to me (and yes, I'm aware that human intuition counts for very little in that context!)
by The Geoff
Sat Jun 15, 2013 2:52 pm UTC
Forum: Science
Topic: sabotage of space
Replies: 17
Views: 5932

Re: sabotage of space

In the real world (yeah, I know, sorry) the issue is complicated by the economics of it all. If you're spending a billion dollars on a single satellite and there's a 10% chance of it being taken out in any given year then that's quite a risk. If you're sending up a bunch of football sized satellites...
by The Geoff
Thu Jun 06, 2013 9:28 pm UTC
Forum: Science
Topic: Size of the observeable universe
Replies: 31
Views: 8895

Re: Size of the observeable universe

I understand why matter clumps, which is why that wasn't at all the question I asked. If there is a finite amount of matter, however large, in an infinite universe, then it is either infinitely divisible (contrary to everything modern science says about fundamental particles), or by mathematical ne...

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