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Physics, Astronomy & Cosmology / MOVED: Re: What are electrons?

« on: 02/06/2014 10:36:27 »

This topic has been moved to New Theories.

http://www.thenakedscientists.com/forum/index.php?topic=51512.0

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Physics, Astronomy & Cosmology / Does a charged black hole emit an electric field?

« on: 18/01/2012 17:34:57 »

There have been a few questions about charged black holes lately, but I think this very basic question about them hasn't been answered yet.  Will a charged black hole (let's say non-rotating for simplicity) emit an electric field and why/why not?  (I'm talking about the black hole itself, not any field that might be emitted by infalling matter).

By the way, I found the site below on the gravitational forces in a charged black hole (but not the field) and it's fascinating.  The charge makes it behave quite differently than an uncharged black hole.  http://jila.colorado.edu/~ajsh/insidebh/rn.html

3

New Theories / Why no aether? (New Theories version)

« on: 04/01/2012 23:51:43 »

This is a redirect from here: http://www.thenakedscientists.com/forum/index.php?msg=376875

The question is, we know that "aether" as used in physics text was a theory that assumed that space is filled with some stuff through which light propagates much in the way sound propagates through air.  Because of this, if you're stationary in the aether, the speed of light should look constant in all directions, but if you're not stationary, the speed of light is no longer going to appear constant in all directions.

Phractality and David Cooper brought up the idea that you could keep the idea of "stuff" (I'm hesitant to say aether because it has a very particular definition that was disproved by MM), through which light propagates if you introduce Lorentz transformations.  To have a better place to discuss this theory (and give us leeway to go off into New Theories), I've put this post here. 

My question regarding this idea is--does this in any way differ from introducing special relativity and Lorentz transformations other than philosophically?  This stuff through which light propagates is going to be unlike any matter we know of, since Lorentz transformations keep it stationary in all reference frames--a property that nothing else has.  Is this a testable hypothesis that differs in any way from special relativity?

4

Physics, Astronomy & Cosmology / Faster than light neutrinos?

« on: 22/09/2011 22:31:40 »

Ok, this isn't really a question.  It's more of a discussion topic.  I don't know if you've seen the news, but apparently scientists at CERN claim to have seen particles (neutrinos) moving faster than the speed of light.  This would obviously be a big deal, since it would cause major problems for special relativity.

Here's a link to the news:
http://www.reuters.com/article/2011/09/22/science-light-idUSL5E7KM4CW20110922

And here's a link to tomorrow's talk (streamed live on the web):
http://indico.cern.ch/conferenceDisplay.py?confId=155620

So... are we going to have to rethink relativity or is this a case of an error in the measurements?

5

Chemistry / How does salt and vinegar work to clean tarnished metal?

« on: 02/08/2011 18:50:25 »

This is inspired by the question on using vinegar to clean rust off metal: http://www.thenakedscientists.com/forum/index.php?topic=40446.msg363843#msg363843

The last time I had to clean some tarnished metal (I believe it was brass), I Googled around for instructions and came across a few sites saying that mixing salt and vinegar would work (with flour to make it a good scrubbing paste).  Lo and behold, it did!  I also recall that as a child, I would often drop dirty pennies into salt and vinegar in order to make them look shiny and new.

So aside from tasting great on chips (either the American or British varieties), what chemistry makes this combination so good at cleaning metal?

6

Just Chat! / Seriously, CNN?

« on: 15/05/2011 07:10:19 »

This was on CNN.com's front page this morning: http://edition.cnn.com/2011/SHOWBIZ/celebrity.news.gossip/05/14/michael.jackson.photos/index.html?hpt=P1

Ignoring the part about the Michael Jackson photos, they don't seem to find any problem with the fact that this guy is claiming to have discovered a perpetual motion engine...   [V]

7

The Environment / Is there a relation between changes in the earth's magnetic field and climate?

« on: 06/05/2011 22:12:02 »

JimBob brought up an interesting point in another thread recently: that the earth's magnetic field shields us from a lot of solar particles.  I don't know if these particles carry enough energy to effect the earth's climate, but if they did, you would probably expect to see climate shifts in the historical record corresponding with periods when the earth's magnetic field shifted polarity (http://en.wikipedia.org/wiki/Pole_reversal). 

So my question is: is there any evidence for climate change correlating to magnetic pole reversal?

A secondary question might be: is there any evidence that a weaker magnetic field on a short-term time scale (not long enough to strip the atmosphere) would lead to major climate change, or do the particles it protects us from not have a strong influence on climate?

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That CAN'T be true! / MOVED: The Mafia and there philosophy...

« on: 05/05/2011 15:50:10 »

Since this forum is for posting "unbelievable science or medicine fact(s)" I'm moving this to
 Just Chat !.

http://www.thenakedscientists.com/forum/index.php?topic=39098.0

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That CAN'T be true! / MOVED: The Goat, and their Philosophy, in relation to social standing....

« on: 05/05/2011 15:49:21 »

Since this forum is for posting "unbelievable science or medicine fact(s)" I'm moving this to
 Just Chat !.

http://www.thenakedscientists.com/forum/index.php?topic=39105.0

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Just Chat! / Website article about an important scientific paper!

« on: 28/09/2010 06:50:11 »

See here:
http://www.guardian.co.uk/science/the-lay-scientist/2010/sep/24/1

Also

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Physics, Astronomy & Cosmology / What are some alternative to string theory? Do they offer testable results?

« on: 28/09/2010 03:09:54 »

This is a tangent I'd like to take from a recent string theory thread.  As far as I can tell, string theory is basically a result of trying to unify quantum mechanics and gravity, and from that attempt have come the ideas of multiple extra dimensions (beyond 4) as well as multiple possible universe.  The main drawback is that its not offering much in the way of testable results, and there's been a lot of debate over whether it's more science or philosophy because of that.

Let's put aside debates on the testability of string theory for now.  I'm curious about some of the alternative attempts to unify quantum mechanics and gravity.  I've heard of at least one, quantum loop gravity.  I don't know much about it, but it also doesn't seem to offer testable results.  What are some of the others?  Do they offer testability that's lacking in the more publicized theories?

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Just Chat! / Neat animations of complicated mechanisms

« on: 31/08/2010 09:17:44 »

Someone sent me this today.  I figured it might be appreciated here.  It's the first time I've actually understood how a sewing machine works!


http://mytechnologyworld9.blogspot.com/2010/08/complicated-mechanisms-explained-in.html

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Technology / What's the difference between a potentiometer and a voltmeter?

« on: 28/07/2010 04:43:48 »

I haven't done lab work in ages, but I seem to recall both names being used to describe things we used to measure voltage.  (Don't hold me to that, though!)  Wikipedia has a link describing the use of a potentiometer as a voltmeter.  From reading the page briefly, it sounds like the potentiometer taps off (a variable amount) of current from a circuit to measure voltage, while a voltmeter isn't variable, and is usually designed to tap off as little current as possible.  Am I right in thinking this? 

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Just Chat! / Something for the mad scientist in your life...

« on: 11/05/2010 06:19:31 »

A hand item for powering your doomsday device:
Uranium ore!

The rest of this list is pretty funny as well:
http://www.amazon.com/Funniest-Amazon-Product-Reviews/lm/RM0256CJKINZJ
Some of the reviews of these items are classic.

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Physics, Astronomy & Cosmology / What are evanescent waves?

« on: 13/04/2010 09:57:35 »

This came up out of a recent discussion on why gravity bends light.  The questions are these: With regards to light/electromagnetism, what are evanescent waves?  Why are they important?  How can we explain them classically and/or quantum mechanically?

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Physics, Astronomy & Cosmology / How do we define the second?

« on: 24/03/2010 04:48:00 »

How is the second defined?  What physical process(es) are we measuring?

(This was brought up in the thread here: http://www.thenakedscientists.com/forum/index.php?topic=29238.0;topicseen
I wasn't quite following the discussion in that other thread, so I thought to make the point clearer we could discuss the point here.)

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Physics, Astronomy & Cosmology / MOVED: time machine calculation?

« on: 23/03/2010 02:24:25 »

This topic has been moved to Just Chat !.

http://www.thenakedscientists.com/forum/index.php?topic=30688.0

(I moved this because it's a mathematical puzzle, not about the physics involved.)

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Physiology & Medicine / Does body mass index (BMI) take race into account ?

« on: 14/02/2010 08:05:15 »

The other day I saw a site (from a hospital), with details on their programs for maintaining healthy weight.  They had categories for "caucasian" and "asian" with two different BMI charts.  So my question is: are there significant differences in what is considered a healthy BMI for people of different races/ethnicities? 

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Physics, Astronomy & Cosmology / Do electrons rotate?

« on: 14/02/2010 07:02:02 »

This topic came up in another thread recently: http://www.thenakedscientists.com/forum/index.php?topic=27444.0

Since it's gotten a lot of discussion, I think it deserves its own thread.  So the question is this: do electrons necessarily rotate?  What kinds of rotation do electrons experience?  Are there physical consequences of these rotations?

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Physiology & Medicine / Any idea what might cause flickering vision with morning exercise?

« on: 22/05/2009 20:44:03 »

I'm not a morning person at all.  I'm not much use until I have my morning  coffee or tea.  However, when my schedule requires it, I sometimes go running in the morning.  I've noticed that when I do so, I get a slight flickering in the center of my vision in both eyes.  It seems kind of like  the flickering you can see from a fluorescent light that's going bad.  It's hardly noticeable with my eyes open, but it's quite distinct if I close my eyes.  I've never had this effect when running at other times of day, or on mornings when I don't exercise.  I'm not particularly worried about it, but I'm curious what might cause it.  Any ideas?