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Saturday, October 1, 2016

Is there an element/compound that is denser as a gas than it is as a solid?

Is there an element/compound that is denser as a gas than it is as a solid?


Is there an element/compound that is denser as a gas than it is as a solid?

Posted: 30 Sep 2016 08:29 PM PDT

If plant life existed on mars in the past, would there still be coal/oil under the surface today?

Posted: 30 Sep 2016 07:03 PM PDT

Since the QT interval represents the depolarization AND repolarization of the ventricles, is it linearly correlated with heart rate?

Posted: 30 Sep 2016 07:43 PM PDT

Are there numbers outside of C? If so, is there an ensemble including every other number ensemble we know?

Posted: 01 Oct 2016 01:32 AM PDT

Just started learning about complex numbers in math class in high school, and asked my teacher if C included all the numbers we know, and she told me it doesn't, but she can't really tell me more about it. I asked the same question to my brother who's in studying math in university, and he told me the same thing. So, what are the non-complex number ensembles, and is there a number ensemble that includes all the complex and non-complex numbers?

submitted by /u/MrEvilNES
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Could roadways contribute to rising global temperature, to a significant degree?

Posted: 30 Sep 2016 01:12 PM PDT

I've heard the theory that enough solar energy hits United States roadways to power all of the America's energy needs.

To me it seems this black surface area absorbs a tremendous amount of heat energy. Whereas it would otherwise be converted to chemical energy (plants), reflected back to space (snow), or halfway reflected (dirt, other).

While certainly not the largest contributor, can this be a factor for rising global temperature?

submitted by /u/MuphynManOG
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What makes a nuclear reaction a direct reaction or a compound reaction (non-resonant vs resonant)?

Posted: 30 Sep 2016 07:33 PM PDT

According to this website, nuclear reactions can be classified as direct or compound. I understand the distinction between the two, but what causes a given reaction to direct/compound? Can the reaction's type be predicted without performing the reaction?

submitted by /u/onlyhtml
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If dirt on Earth is called "earth", what is dirt on Mars called?

Posted: 30 Sep 2016 11:49 AM PDT

If movement is relative, and F=ma, does that mean that force is also relative?

Posted: 30 Sep 2016 05:42 PM PDT

Are we able to see black holes? If so, can we see the Milky Way's black hole (from earth/telescope)?

Posted: 30 Sep 2016 05:45 PM PDT

What's happening on a molecular level that makes pasta so sticky?

Posted: 30 Sep 2016 04:39 PM PDT

If I were placed into a hollow sphere with super-massive walls, would I experience time dilation but not gravity?

Posted: 30 Sep 2016 05:27 PM PDT

Can you tell if two chemicals will react just by their names?

Posted: 30 Sep 2016 05:15 PM PDT

Im curious if there is a general method in determining whether a chemical compound is compatible or not with another simply through means of their names. For example would all silicones melt in all esters? Would different esters be compatible simply because they are both esters? Would fluorosilicone be affected by silicone based fluids? Etc Etc. Please explain simply, only have basic chemical knowledge. Thanks

submitted by /u/chem689
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Why do Galaxies look like spirals?

Posted: 30 Sep 2016 07:50 AM PDT

I'm pretty sure that it actually spirals because the center is rotating faster due to being closer to the core, so its a spiral as opposed to more of a star. But I'm not ever sure if that's true.

My main question is why do they get that sort of shape in the first part, shouldn't the settle as more of a disk? What causes the arms to form?

submitted by /u/PM_me_your_spacegoat
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Are there any ecosystems relatively immune to global warming?

Posted: 30 Sep 2016 11:12 AM PDT

Why does matter accreting onto a white dwarf cause it to go nova, and not just "reignite" into a regular star again?

Posted: 30 Sep 2016 07:01 PM PDT

For those that can lipread, is it possible to distinguish regional or international accents by using solely lipreading?

Posted: 30 Sep 2016 09:56 AM PDT

Do metals/alloys resonate electrically like quartz and other crystals do?

Posted: 30 Sep 2016 12:05 PM PDT

I know that quartz crystals can be made to oscillate electrically, and for this reason are used as high-Q filters for the feedback paths of electrical oscillators. Is there a similar resonant property for metals (obviously not piezoelectric)? I know that the quartz resonant frequency is influenced by its dimensions, so I'd be looking for something more intrinsic to the metallic structure itself (independent of overall geometry). For instance, if I am presented with a sample claimed to be 70% gold, with the remainder being copper, is there any way to test that electrically? Something like "The impedance of such an alloy would have a peak/trough at 770MHz. The actual peak was measured at 760MHz, indicating only 60% gold."

submitted by /u/averazul
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How do we know that young earth was hot and molten?

Posted: 30 Sep 2016 11:44 AM PDT

The Rosetta mission provided a lot of evidence about how the young solar system formed, including the aggregation of dust particles to produce larger objects. They also discussed the source of earth's water. Some research suggests it must be extra-terrestrial since the young earth was hot and molten and water would have boiled off. But I can't find what the evidence is for a hot molten young earth (except perhaps after the proto-moon collision). How do we know the earth didn't simply form by the cold accretion of particles from the nebula, eventually heating the core, but not the surface? Related, if everything formed from the planetary nebula, why is the H-D ratio different in different objects?

submitted by /u/stickylava
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Do the lack of BSL-3 facilities worldwide increase the risk of a worldwide epidemic? Why exactly do we not have more of these facilities?

Posted: 30 Sep 2016 07:48 AM PDT

As the titles states.

submitted by /u/perkam
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Friday, September 30, 2016

How many times do most galaxies rotate in their lifetimes?

How many times do most galaxies rotate in their lifetimes?


How many times do most galaxies rotate in their lifetimes?

Posted: 30 Sep 2016 04:58 AM PDT

When an object is travelling at speed, at what point does it go from being cooled (by air resistance) to heating up and eventually burning up?

Posted: 29 Sep 2016 05:41 PM PDT

When I ride my motorbike at 100km an hour, the air cools me and the bike, when a rocket re-enters the earths atmosphere, it appears to heat up. Is there an exact speed at which this happend?

submitted by /u/Theplayground_nz
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How do quantum computers get programmed?

Posted: 30 Sep 2016 05:05 AM PDT

It's mor a "Where is the program saved and where can we save the results from the programms?" question, but the real programming is interesting as well. I don't thin they use Java or something like that ^

submitted by /u/Simyala
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Are any of Einstein's predictions yet unproven, and if so, which would be the most groundbreaking if proven correct?

Posted: 29 Sep 2016 02:27 PM PDT

Over 100 years after they were predicted by General Relativity, gravitational waves were observed by LIGO last year. Are there any more of his predictions floating out there?

submitted by /u/sonofdarth
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What is generally used to cool down superconductive elements?

Posted: 29 Sep 2016 08:01 AM PDT

Not just in labs, I'd like to know what is used outside of it because I figure that labs probably use some way that is really effective but also expensive, which is logical, but unuseable in other ways beacuse of the cost, so I'm wondering what it is that does the trick for the outside of the lab use.

EDIT: Thanks, I've been wondering for some time so I asked here rather than browse and possibly end up with wrong info.

submitted by /u/slimreaperokc
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When a supernova explode and collapse to a black hole, how much time does it takes from explosion to being a singularity ?

Posted: 29 Sep 2016 02:17 PM PDT

Is the speed of the density increase constant, accelerated, decelerated ?

In the time frame of a distant external observer

submitted by /u/vilette
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Would our sun (Sol) be visible from Alpha Centauri?

Posted: 29 Sep 2016 06:55 PM PDT

Imagine an Earth like planet with an Earth like atmosphere in orbit around one of the stars in the Alpha Centauri system. Correct me if I'm wrong but on a cosmic scale it wouldn't make a huge amount of difference which star this planet is in orbit around.

Would our star be visible to the unaided eye from this planet?

submitted by /u/Starzajo
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For a series circuit with a voltage source and three resistors, after current flows through all resistors, why does the voltage drop to zero?

Posted: 30 Sep 2016 06:49 AM PDT

Voltage drops across every resistor. Say for example we have a 12V power source and after going through three resistors with 3ohms each, the 12V drops by 4V per resistor until it reaches zero. But is it really zero? Say, if we connect a fourth resistor after the third resistor, shouldn't there be a voltage reading across the fourth resistor? What should be the voltage value after going across three resistors if not zero?

submitted by /u/xHamsaplou
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How are aqueous solutions of metal ions prepared?

Posted: 30 Sep 2016 06:14 AM PDT

I'm curious how they come up with these at chem problems.

submitted by /u/Ytonic
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What would happen with two telescopes?

Posted: 29 Sep 2016 05:12 PM PDT

If you had one telescope and were able to zoom into the viewfinder of another telescope situated far away? Would you have a view of what the person looking through the second telescope would see, or would it be the combined magnification of the two telescopes?

submitted by /u/gmikoner
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When searching for exoplanets, do astronomers have to account for the planets size?

Posted: 29 Sep 2016 04:25 PM PDT

I was always taught in school that the more mass an object has, the stronger its gravitational force becomes. Does that mean that exoplanets that are considered habitable have to be within a certain mass range so that are bodies don't just collapse from gravitational pull; like they would if you could theoretically go onto a neutron star?

submitted by /u/Mythicdream
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Now that the Earth and Moon have been tidally locked for a decent while, what interesting differences can we find between the Regolith (or deeper layers) on either "side" of the moon?

Posted: 29 Sep 2016 03:53 PM PDT

Are there any promising New ways to fight antibiotic resistance in bacteria?

Posted: 29 Sep 2016 04:47 PM PDT

I know there is some interesting research into new antibiotics for which there are no resistance yet, but what seems to be the most interesting tool aside from that to fight these bacteria?

submitted by /u/flaptamer
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Whаt сausеs осulаr dоmіnаnсе?

Posted: 29 Sep 2016 03:21 PM PDT

How does olfactory fatigue work?

Posted: 29 Sep 2016 04:25 PM PDT

I can't seem to find specific scientific information about how it exactly works. Do we not really know? Or am I just bad at googling?

The wikipedia page is surprisingly lacking...

(specific as in what happens at the molecular level)

submitted by /u/RaidenXT
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When does a star 'ignite' and is it instantaneous?

Posted: 29 Sep 2016 12:28 PM PDT

How stable are the Lagrange points?

Posted: 29 Sep 2016 12:52 PM PDT

We know that L1, L2, and L3 are inherently unstable, whereas L4 and L5 are stable. But how much does it take to actually affect the equilibrium of an object in an unstable Lagrange point?

Let's say we have a ship parked at L1 between the Sun and the Earth. Now if this ship was to move a little closer to the Sun, its gravitational pull would obviously pick up, and the ship would inevitably fall towards the sun. But how much instability are we talking about?

Astronomical scales are pretty huge in general, but how much displacement would it take to affect the ship's equilibrium? Is it in the order of the meter? Kilometer? Megameter?

submitted by /u/justbourv
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In DC power transmission down a wire, what is really transmitting the power, the electrons slowly bumping along, or the photons propagating the EM field?

Posted: 29 Sep 2016 11:57 AM PDT

Who is the real hero? I'm guessing it's more complicated then this, does my question even make sense?

submitted by /u/spectralwarp
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Is it possible to pick 6 colors with the most amount of contrast between them?

Posted: 29 Sep 2016 11:57 AM PDT

Not sure if this is in the right sub, or if it's the right flair. Shout-out to /r/cubers!

I'm asking this because I solve Rubik's Cubes and the like as a hobby. A common thing to do is to swap out the stickers on your cubes to increase the contrast between them so that color recognition is easier.

My question is, is there a set of 6 colors that is optimally contrasted from one another?

submitted by /u/AldersRazor
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If an object is in orbit, meaning it is in free-fall, what stops it from accelerating indefinitely?

Posted: 29 Sep 2016 03:53 PM PDT

What are the greatest pros and cons of MOND, Teves, and Conformal Gravity?

Posted: 29 Sep 2016 09:48 AM PDT

I am currently working on comparing these theories in relation to large cluster rotation and a few other areas. I am really new to this research so I was just hoping to see if I could get some back and forth on the topic along with all the articles and presentations I have been reading/watching. I have a good grasp on the concepts of each but the math isn't totally clear to me yet so I apologize for that. Thanks!

submitted by /u/omniacgames
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How does the decibel system in water compare to in air? Do humans perceive things to be louder underwater?

Posted: 29 Sep 2016 09:45 AM PDT

Sperm whales are known to produce sounds of over 200 dB. Is this the same thing as 200 dB in air? Would it burst my eardrums if I was close to the whale?

submitted by /u/spdalton
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With new experiments showing the speed of light isn't constant, what does this mean for relativity?

Posted: 29 Sep 2016 11:35 AM PDT

Reference: https://www.sciencenews.org/article/speed-light-not-so-constant-after-all

I'm naive on this subject so, somebody please explain how this could affect our theory of relativity.

submitted by /u/Xacto01
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Thursday, September 29, 2016

Why do we keep trying to find new heavy elements if they only snap into existence for milliseconds?

Why do we keep trying to find new heavy elements if they only snap into existence for milliseconds?


Why do we keep trying to find new heavy elements if they only snap into existence for milliseconds?

Posted: 28 Sep 2016 06:31 AM PDT

Would these super-heavy elements have some use? Is it self-assurance?

Thanks for the help, I'm only a sophomore in high school, but I'm super interested in this kind of science so try not to use to big of words, I think I have a somewhat basic understanding though.

Again, Thanks! :)

submitted by /u/XxCjkavyxX
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Since gravitational waves are real, does that mean all gravitational orbits are decaying?

Posted: 29 Sep 2016 05:15 AM PDT

As the waves would use up energy

submitted by /u/TriangleGodsDenyYou
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How did people measure light intensity before electronics existed?

Posted: 28 Sep 2016 07:25 PM PDT

One of the reasons Quantum Mechanics was first created was that the intensity of light radiated from black body did not agree with the intensity predicted by the Rayleigh-Jeans equation. My question ii: How could they reliably measure the intensity of emmited light for each wavelength?

submitted by /u/isnar000
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How can astronomers tell that a star is about to supernova?

Posted: 29 Sep 2016 07:24 AM PDT

Specifically, how does a star behave right before it will supernova? Does the star begin to emit more neutrinos? Does its apparent size get smaller? Do the orbits of nearby planetary bodies change?

submitted by /u/IWishIwasInCompSci
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is there a critical mass at which an object in space can no longer be non-spherical and collapses under its own gravity?

Posted: 29 Sep 2016 04:49 AM PDT

since i think it will most likely depend on the material lets say the object is made out of your average space rock/dust?

submitted by /u/Once-a-lurker
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How do you explain this halo around the shadow in the image?

Posted: 28 Sep 2016 03:59 PM PDT

The shadow of this plane has a halo around it, the light looks diffracted and appears to only show the red and yellow...

How do you explain the circular shape and diffraction of light around the shadow?

submitted by /u/CyndaquilTurd
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Can we model the half-life of an isotope by isotopic characteristics?

Posted: 28 Sep 2016 04:31 PM PDT

I tried searching to no success.

Can we model the half-life of an isotope by isotopic characteristics? Is an isotope's half-life duration a product of its number of protons, neutrons, electrons, some function thereof, or some other quantifiable observation? Or do we not know yet?

submitted by /u/ValleyForge
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Are any two given temperatures guaranteed to have every temperature between them?

Posted: 28 Sep 2016 12:04 PM PDT

For example: if my hotpocket is 600 degrees in the middle, and 2 degrees on the outside, am i guaranteed to find every temperature between 2 and 600 in the hotpocket?

submitted by /u/__Sanctuary__
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Do crystal models of bulk solids work for describing everyday materials?

Posted: 28 Sep 2016 07:13 AM PDT

In my studies of condensed matter/solid state physics, we always model materials as fairly simple crystal lattices. This obviously works well for metals and things like diamond, but can these models be applied to everyday materials like wood and plastic? My instinct says no since these are made of complex molecules. What other models are there for describing the bulk properties of everyday complex solids?

submitted by /u/nottherealslash
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Where could we settle on Mars?

Posted: 27 Sep 2016 06:23 PM PDT

Where are likely candidates for landing and colonization? What are the criteria that NASA and SpaceX are looking at? What are your initial impressions of the feasibility of this? Asking because of this: https://www.youtube.com/watch?v=0qo78R_yYFA

submitted by /u/blue-footed_buffalo
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