Pages

Thursday, May 19, 2016

Would headphones tangle in space?

Would headphones tangle in space?

Would headphones tangle in space?

Posted: 19 May 2016 01:11 AM PDT

My guess is that the weight of the cables in a confined space (eg a pocket) acts on tangling them. If they are confined when they are weightless would the cable not just stay separated? Entropy?

submitted by /u/OrangeCloud26
[link] [comments]

How long does it take for a human body to totaly disappear in the ocean (water)?

Posted: 19 May 2016 01:06 AM PDT

*totally

So I was reading about the Malaysian airplane that disappeared two years ago and about the debris they think they found.

If the people died in a crash, would the bodies decompose because of the water (with help of the water)?

submitted by /u/aknavi
[link] [comments]

Standard Candles (Cepheid Variables, Type 1a supernovae) are relatively common. Apparently 'Standard Rods' exist but are extremely rare- what are some examples of Standard Rods?

Posted: 18 May 2016 03:39 PM PDT

The cosmology course i'm studying right now mentions very briefly that standard rods exist. I'm intrigued, but can't find any examples online. Can any astronomers help?

submitted by /u/chapmouse
[link] [comments]

What's the difference between a mutagen and a carcinogen?

Posted: 18 May 2016 06:59 PM PDT

I work with ethidium bromide in the lab, and was told that it was a mutagen by my professor. He said he's not sure why it's not considered a carcinogen, as cancers are caused my mutations, and the mutagen causes mutations. Can anyone clarify?

submitted by /u/Adamtype1
[link] [comments]

If we were to see a black hole up close, would we be able to see everything that fell into it on the event horizon?

Posted: 18 May 2016 09:15 PM PDT

I remember being told that if you were to watch someone fall into a black hole, at a certain point they would seem frozen in place forever (as light can't escape beyond this point).

If a lot of stuff has fallen into a black hole, would we see a jumble of clutter at the event horizon of everything that has ever fallen in?

I'm imagining a static version of the win screen of the old solitaire on Windows (https://www.winningsolitaire.com/)

submitted by /u/deskplace
[link] [comments]

Can I smooth this rock with just my hand?

Posted: 18 May 2016 10:46 PM PDT

This specific rock. I want to smooth it until the sharp edges are gone and it resembles this. As a meditation in restraint, I want to do so purely by hand. I mean with my hand, not with hand tools. From those pictures (sorry for the quality) and without any kind of chemical assessment, would one of you geologists with wizardly powers identify the kind of rock? If it helps, it was sourced from the beach of Whidbey Island in Washington State. Would I be able to smooth it by hand in a couple weeks, months, years, ever? Or am I just going to be rubbing my hand raw? I mean, that would still be a valid exercise, but my hope is that it's possible, and hpoefully in some very short timeframe. I was planning on doing so just about any time I have a free hand (lunch, on the bus, reading in bed). Thank you for any help, even if it's just a tip that there's another subreddit I should post in!

submitted by /u/Khenghis_Ghan
[link] [comments]

Composition of the Moon: Why So Plain?

Posted: 18 May 2016 07:58 PM PDT

If the Moon was formed from the Earth after a comet or planet strike then why is its composition nothing like Earth's? I've heard that lunar regolith described as being like ground glass, very sharp, etc. Now this can be explained by the lack of erosion processes, however that brings up another question. Why does it not have water or even a light atmosphere if it was borrowed from Earth?

submitted by /u/Nexus_666
[link] [comments]

Does Earth's annual tilt that creates summer and winter affect geostationary satellites?

Posted: 18 May 2016 10:48 PM PDT

Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology

Posted: 18 May 2016 08:04 AM PDT

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Biology, Chemistry, Neuroscience, Medicine, Psychology

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions.

The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here.

Ask away!

submitted by /u/AutoModerator
[link] [comments]

What is the reason for the Dark Matter/Dark Energy hypothesis?

Posted: 18 May 2016 01:38 PM PDT

In particular,it seems like there was a view of the way the universe worked (Big Bang, Expanding and/or contracting universe, etc.), what problem came up that made someone propose Dark matter and/or Dark Energy as a solution?

submitted by /u/fellfire
[link] [comments]

Creating suction with gravity ?

Posted: 18 May 2016 03:05 PM PDT

Is there a way to create suction using an elevated liquid source and a pipe system that flows from the bottom of the container and wraps under then above? A self sustaining waterfall so to speak.

submitted by /u/felixthejosh
[link] [comments]

How do animals know where to strike?

Posted: 18 May 2016 07:11 PM PDT

Like when wolves throat clamp or when animals know you're making eye contact, how do they know it?

submitted by /u/evil_basturd125
[link] [comments]

When I'm wearing polarized sunglasses, why does the sky change brightness when I tilt my head?

Posted: 18 May 2016 10:09 AM PDT

I know the sky scatters light but I only notice a change in brightness closer to the horizon.

submitted by /u/Bigmitch2
[link] [comments]
vào lúc No comments:

Wednesday, May 18, 2016

PLOS Science Wednesday: Hi Reddit, we are Florian Markowetz and James Breton. We published a paper in PLOS Medicine showing resistance to cancer treatment may be related to the heterogeneity in the tumor, which has implications for drug effectiveness – Ask Us Anything!

PLOS Science Wednesday: Hi Reddit, we are Florian Markowetz and James Breton. We published a paper in PLOS Medicine showing resistance to cancer treatment may be related to the heterogeneity in the tumor, which has implications for drug effectiveness – Ask Us Anything!

PLOS Science Wednesday: Hi Reddit, we are Florian Markowetz and James Breton. We published a paper in PLOS Medicine showing resistance to cancer treatment may be related to the heterogeneity in the tumor, which has implications for drug effectiveness – Ask Us Anything!

Posted: 18 May 2016 04:53 AM PDT

Hi Reddit,

My name is Florian Markowetz and I am a cancer researcher at the University of Cambridge in the Cancer Research UK (CRUK) Cambridge Institute. My lab and I try to understand how genetic variability between and within patients leads to differences in cancer progression and outcome.

And my name is James Brenton and I am a senior group leader at the CRUK Cambridge Institute, where I study the functional genomics of ovarian cancer and lead on translational studies in the clinic as a medical oncologist at Cambridge University Hospitals.

We recently published a paper titled "Spatial and temporal heterogeneity in high-grade serous ovarian cancer: a phylogenetic reconstruction" in PLOS Medicine. The main hypothesis that we were trying to test was whether the magnitude of intratumoural heterogeneity in a patient's ovarian cancer was a predictor of their outcome. For this, we developed new methods to parsimoniously reconstruct phylogenies using copy number profiles. We found evidence that resistance to treatment could be linked to the degree of genetic heterogeneity in the tumor. The more heterogeneous a tumor is, the more likely is it that the patient becomes resistant. Our study is small, but it identified what could be one of the key reasons why drugs stop being effective after some time.

We are looking forward to exploring this topic further with you and will be answering your questions at 1pm ET -- Ask Us Anything!

You can find out more about me (Florian) and my research at my lab's webpage and on my blog Scientific B-Sides. And don't forget to follow me on Twitter @markowetzlab.

submitted by /u/PLOSScienceWednesday
[link] [comments]

Modern alternatives to Freud's concept of Id, Ego and Superego?

Posted: 18 May 2016 03:53 AM PDT

Freud's model, since its introduction, hasn't been changed or updated a lot and all modern psychoanalisys works are based on that almost a century old theory.

I'm wondering if there are any alternatives in the modern psychology that explain the human psyche differently/more in depth, or taking into account current discoveries in the field of psychology?

For instance, I'd like to know how such things as defensive mechanisms, primitive biologically based and survival instincts are being interpreted and linked to the human psyche nowadays.

Thanks in advance.

submitted by /u/Reddit4iphone
[link] [comments]

If a commercial airplane has both engines fail at cruising altitude, how far can it glide in an attempt to find a safe place to land?

Posted: 17 May 2016 07:38 PM PDT

What is the time elapsed in a nuclear detonation?

Posted: 18 May 2016 02:58 AM PDT

All I can find is speed of the shockwave, but how fast is the nuclear reaction going? I'm guessing the atomic fission occurs on the order of nanoseconds. Also, the violence of the detonation is because of the fast energy release, so then if the event could occur in, say, attoseconds, would that mean an even greater force? Conversely, if it were slowed down to "one hour" let's say, then what would that look like?

submitted by /u/Haf-to-pee
[link] [comments]

Why is 0! greater than 0.5! ?

Posted: 17 May 2016 07:13 PM PDT

When I type 0.5! into my calculator, I get 0.8862.... But when I type 0! into my calculator, it gives me 1. How can a factorial of a smaller number be larger than a factorial of a larger number? I understand whole number factorials, but I don't understand decimal factorials at all. Also, how is it possible to have a factorial of a non-whole number? Is there some advanced way of defining factorials that we aren't taught in highschool?

submitted by /u/l0__0I
[link] [comments]

Can we emulate the superposition of quantum computers in a standard computing?

Posted: 17 May 2016 08:48 PM PDT

Hey /r/askscience, I searched and I could not find my question asked or answered. Is it possible to emulate the superposition of quantum computers in standard computing? My very basic (and perhaps flawed) understanding of quantum computers is that due to the nature of quantum particles, qubits could be both on and off at the same time, letting the computer compute both the on and off state at the same time. Why can we not do this with standard computing by not observing the bit and assuming a both on and off state?

submitted by /u/GarryLumpkins
[link] [comments]

Would temperature affect the duration and frequency of water rippling?

Posted: 17 May 2016 08:47 PM PDT

For example does warm water (lets just say 100°F) ripple longer or at a different frequency than cold water( maybe around 60°F)? I am genuinely curious if thermodynamics plays a big role in this or not.

submitted by /u/TomsShow
[link] [comments]

How was pi first calculated? How is it calculated now?

Posted: 18 May 2016 02:52 AM PDT

What does "structure of lowest energy" mean?

Posted: 18 May 2016 01:29 AM PDT

How come: low surface area => low energy?

see 10 seconds of the video linked below

https://youtu.be/UUkVMvJqALk?t=11s

submitted by /u/sebaris
[link] [comments]

How Did Life Begin?

Posted: 18 May 2016 04:23 AM PDT

Why is a sodium-potassium alloy more reactive than either metal alone?

Posted: 17 May 2016 08:31 PM PDT

Pretty much the title. Noticed this Popular Mechanics article where someone's playing with alkali metal bullets, and I'm curious as to why the Na:K alloy seems to react more violently with water(melons) than pure sodium or potassium.

submitted by /u/onwardtowaffles
[link] [comments]

Does the discovery of a new element require the nucleus to be surrounded in its ground-state electron configuration or is it sufficient to just synthesize the nucleus?

Posted: 17 May 2016 07:05 AM PDT

Put another way, what is the highest mass number atom (i.e. not a charged ion) that has ever been synthesized?

submitted by /u/moomin100
[link] [comments]

Looked up "chirp mass" on Wikipedia and it leaves out the juicy part: why is it called a chirp mass?

Posted: 17 May 2016 06:44 PM PDT

It's not capitalized, it doesn't have its own entry...what the hell, astrophysicists?

submitted by /u/Wisdom_from_the_Ages
[link] [comments]

Can light ever reach Earth (or any celestial body) from a star that originated it?

Posted: 17 May 2016 07:28 PM PDT

Not sure how it could happen, but I'm imagining that refraction causes the light to move farther than the displacement of the planetary object moving obv slower than light?

If possible, we'd literally be able to see what we were before we were here.

submitted by /u/1zee
[link] [comments]

Conceptual explanation for the sum of all natural numbers (1+2+3=-1/12)?

Posted: 17 May 2016 03:57 PM PDT

Sooooo.... I was looking for advice on my dating profile and everyone freaked out about the "sum of natural numbers "(I had it listed on my things I think about). And now I'm a bit concerned because I show this example to my high schoolers when they ask me to blow their minds and I want to make share I'm not misleading them when I explain this to them conceptually. I understand there are rigorous proofs, hand wavy proofs, controversial proofs, BUT, I want to see if this makes sense conceptually as this is how I've been explaining it to my students.

  • Ok so I generally use the proof from that numberphile video with the physicists. So if we take the series ,1-1+1-1+... and we were to use it model a light switch and consider on=1 and off=0 and we keep flipping the light switch on and off (for infinity) then the total number of photons, the total intensity, the total luminosity in the room is 1/2 what it would normally be at any moment in time (avoiding any sort of multi-photon or non-linear effect) and this is true as long as the switch is being flipped on and off. As soon as you stop, this no longer represents an infinite process and will equal either 1 or 0. Is this okay? Is this an accurate description/analogy?

  • Secondly, if that conceptual example is satisfactory then can we say the same of the sum of all natural numbers? It is not a trick, or a fallacy but a meaningful answer that is only true within the context of a problem and is only true when the process in question is infinite?

  • Third, is it fair to say that the answer we get is meaningful within the context of a specific problem in a field like Quantum Field Theory, in the same way that an answer like 1/0 would be meaningful in Cosmology?

My kids really get into it and they have taken it upon themselves to try to "prove" other infinite series on their own. Its pretty amazing. Their answers are WRONG, but the effort and the spike in their level of interest, specifically in math, is insane. I'd like to keep using it. Anyway, thanks for reading and for any insight you can offer.

submitted by /u/Hectur
[link] [comments]

How did commonly found specialized organs such as the liver originally develop?

Posted: 18 May 2016 12:24 AM PDT

The further evolution of these organs seems relatively straightforward, but how did they appear in the first place? Could some form of symbiotic background between organisms have been possible, perhaps leading to horizontal gene transfer?

submitted by /u/tzaeru
[link] [comments]

What is the evolutionary cause for urination and defecation to be two separate bodily functions instead of one combined expulsion?

Posted: 18 May 2016 01:09 AM PDT

How does anesthesia work? What effect does it have on the brain to knock a person out but not allow them to dream?

Posted: 17 May 2016 07:49 AM PDT

I just had surgery (carpal tunnel release) and I was given anesthesia intravenously. I know you can't remember anything that happens, but the odd thing for me is that you can't dream. How does this work, and how does it kick in so fast?

submitted by /u/AnosmiaStinks_ithink
[link] [comments]

What are Tachyons, and what is the likelihood that they really exist? If the do exist, what could the be used for?

Posted: 17 May 2016 04:38 PM PDT

How do butterfly wings work aerodynamically?

Posted: 18 May 2016 04:32 AM PDT

Bird wings bend/fold when moving back up after flapping down, allowing them to move fluidly upwards and preventing them from producing upward force on the air and pushing the bird back down, but butterfly wings are more stiff and don't seem to bend, so how do butterfly wings, when flapped, not push the butterfly back down?

*I wasn't sure which would be the best category for this question, as it would fit under Biology, Engineering, and Physics, so I just went with Physics.

submitted by /u/MRMiller96
[link] [comments]

What happens to Newtonian physics and quantum field theory as your approach Planck's scale?

Posted: 17 May 2016 06:44 AM PDT

Do Newtonian physics General Relativity and quantum field theory gradually become less reliable as you approach Planck's scale (from each respective side)? Is there a point where both can be used with the same reliability, though, neither would be accurate? Or is it like a light switch, in that, suddenly Newtonian physics General Relativity stops working and quantum field theory takes over?

Edit: My mistake. General Relativity not Newtonian physics.

submitted by /u/Existential_Fluff
[link] [comments]

Is degeneracy pressure a non-local phenomenon?

Posted: 17 May 2016 09:50 PM PDT

When you cool and compress a collection of fermions, you will reach a point where it is not possible to compress the fermions further. This is due to the Pauli Exclusion Principle, which in turn is traceable the spin-statistics connection, i.e. the fact that what spin a particle has determines which type of statistics it obeys, whether Bose-Einstein (integer spin) or Pauli-Dirac (non-integer spin).

Where the problem of non-locality comes in is that nothing (such as a field) mediates the spin-statistics connection. It is simply a fact of nature. Doesn't this mean that degeneracy pressure is a non-local phenomenon?

submitted by /u/ManicMarine
[link] [comments]

Since the Earth is not a perfect sphere is gravity different on different places? If so, would that mean time passes differently in those places as well?

Posted: 17 May 2016 01:28 PM PDT
vào lúc No comments:

Tuesday, May 17, 2016

Does the glass on a smartphone screen get thinner over time the more you touch it?

Does the glass on a smartphone screen get thinner over time the more you touch it?

Does the glass on a smartphone screen get thinner over time the more you touch it?

Posted: 16 May 2016 09:46 AM PDT

Where is the line drawn for what counts as one molecule? Is a full strand of DNA one molecule? Is the membrane for the nucleus?

Posted: 17 May 2016 05:14 AM PDT

I've heard grapes have more "coding genes" than humans. Do the human coding-genes form some kind of sub-set or overlap of the grape, or are the coding regions of the DNA/(genome?) completely different?

Posted: 16 May 2016 05:40 AM PDT

My question may not even make sense, because I think of the huge lists of base pairs being kind of like a book with ordered pages, which may not be the case.

But the idea that a grape is more genetically flexible or 'powerful' than us raises so many interesting questions in my (layman's) head:

Could you culture a grape (with perfect gene editing and knowledge) to be a human, but not the other way around?

Have the non-coding genes been found to have more function than 'junk' DNA?

How did the grape get more coding genes, anyway?

Are there generally more coding genes in plants or mammals? Seems counter-intuitive, but then I suppose a mouse is more similar to a human than grass is to a pineapple?

Sorry for the ramble. The main question I have is: Do the "coding genes" fall in roughly the same locations along the genome?

submitted by /u/isaidthisinstead
[link] [comments]

Is Dark Energy a property of spacetime? Can Dark Energy be attributed to the Casimir Effect? Why use Mpl/(Lpl)^3 to discredit QFT explanations of DE? AND MORE!

Posted: 16 May 2016 07:15 PM PDT

Hey guys, I've now wasted my day off exploring our limits of understanding about Dark Energy and now have some questions that, hopefully, you wonderful people can answer for me. For reference, a good chunk of these questions arise from watching Professor Ed Copeland talk about Dark Energy in this video

Professor Copeland makes some assertions about Dark Energy:

  1. It's uniformly spread across the entire universe (its smooth).
  2. It's always been smooth (evenly distributed)
  3. It is not the dominate force in the universe but it will be due to the expansion of the universe. (energy density of matter and radiation drops as space expands)
  4. It weak in local systems with high mater density and strong in systems without a high matter density

On to my questions:

1) Is Dark Energy a property of space-time itself?

  • If DE is uniformly distributed, has always been uniformly distributed, and does not lose energy density as space expands, does this not spell out that space-time expands 'on its own'? It seems to me that the properties of DE are so different from matter or radiation in how they propagate across the universe that DE can't be a 'thing' but rather a property of how space-time acts.

2) If Dark Energy is a property of space-time, why not attribute it to the Casimir Effect?

  • So this question is a little loaded because I know that most physicists would point out that the Casimir Effect is ~7.2x10122 times stronger than DE seems to be. Lets just put that notion aside for a second (don't worry I'm coming back to it). The Casimir Effect is what happens inside a vacuum where particle pairs are spontaneously created from residual energy of the vacuum. These particle/anti-particle pairs are created for only brief periods of time (so short that they are referred to as virtual particles) but still exert a force on the system. Since the Casimir Effect is a property of space-time and will exert pressure, it seems like a great candidate for what DE is.

3) When asked why vacuum energy (Casimir Effect) doesn't explain DE, physicists say its too powerful and give an approximation on the Planck scale as verification

  • As the linked comment shows (I've seen a similar explanation in many other places as well), the classic rebuttal to vacuum energy is that its just way too strong. My problem is why in the world do we use mp/lp3 to explain why it is too strong. The Planck mass (mp) is the highest possible mass for a single-charge quanta and we are dividing it by the smallest possible volume? Why not use a mass of a proton or something much closer to what kind of particles the Casimir Effect produces? To me, if we divide the largest mass possible of a particle by the smallest volume that particle can occupy, of course we're going to get an extremely large number. I guess the question is: why is mp/lp3 used to estimate the Casimir effect?

  • Another thought of mine is: can we work backwards from the strength of DE to find what the Casimir Effect must produce to be similar/analogous to DE? Would this produce a viable result?

  • Tagging on to this, could particles that have m>mp interact with each other to form black holes, thus minimizing the net force of the Casimir Effect? Would these black holes have to evaporate (radiate away) extremely quickly to be viable?

4) If DE can't be contributed to the CE, are there any thoughts on whether space will expand on its own when given energy?

  • I still struggle with DE being something other than a property of space-time so I'm gonna follow that logic train for a bit. Could space-time itself be 'self expanding'? "Empty" space will spontaneously create particles, is there any reason not to think that it could also self-expand with the energy it has? Or maybe space-time is self-repelling? This question is similar to #1 but focuses on space being self-repelling or self-expanding specifically

5) OK, one last question and then I'll be quiet, promise. Why is a 'big-rip' a possibility with our understanding of DE?

  • DE is weak with high matter density systems (eg galaxy, solar system, moon systems, handshakes, etc) so how is it theorized that DE will overcome the strength of gravity and the other 3 forces? I understand local clusters drifting apart and galaxies drifting away from one another, but our galaxy is already held together by gravity. How is DE supposed to break up the milky way if the gravitational forces are too strong for DE to expand the galaxy as is. I guess a better way of putting it is: is our (or any) galaxy expanding due to DE already? If so, why isn't gravity preventing that expansion, isn't gravity currently too strong for DE to 'gain its momentum' and break up the galaxy?

Okay, that was really long, I apologize. I don't expect anyone to answer all the questions, but if you're willing to answer one or more, I'd be very appreciative for your time and investment in my learning.

PS: The bullet points are more or less my thought process behind each question so that you can get a better feel of where I'm at.

submitted by /u/DirtyJesus1
[link] [comments]

Are there galaxies without a black hole in the center?

Posted: 17 May 2016 03:37 AM PDT

How the Schwarzschild Radius Formula was found ?

Posted: 16 May 2016 10:22 AM PDT

I was wondering if anyone could explain how Karl Schwarzschild ended up on this formula( R=2GM/c2) for the Radius to which you must reduce a object to make it a black hole . From what did he started ?

submitted by /u/matoussa71
[link] [comments]

[Mathematics] What type of counting system do we use for time?

Posted: 16 May 2016 11:09 AM PDT

A little googling tells me its a sexagesimal (base 60 counting system) which to me fits fine enough for seconds and minutes, but when you include <microseconds and hours and days and such it becomes more complicated. I would call it a hybrid counting system, base ten for the first digit, base 6 for the second digit, twelve for the next two digits and so on and so forth. Is there an actualy term for this kind of counting system?

submitted by /u/Sman6969
[link] [comments]

what is the concentration of fluoride require to prevent bacterial proliferation?

Posted: 16 May 2016 07:12 AM PDT

I also realize it could depend on the bacteria. So I also want to know how much. Maybe its almost none maybe its a lot.

Chose chemistry since ''biochemistry'' included. I guess cellular biology would not be far either.

submitted by /u/LOST_TALE
[link] [comments]

What does the molecular structure of titanium look like? I can't seem to get a definitive answer using Google.

Posted: 16 May 2016 02:31 PM PDT

I tried Googling titanium molecular structure to mixed results, depending on the type of Titanium.

Here's the thing, I don't know what I'm looking for except that I have one titanium implant in my left ear and some titanium screws in my C spine.

I'd like to use the molecular structure in a piece of artwork I'm working on, but I'm not sure which one I should use.

Any ideas?

submitted by /u/12084182
[link] [comments]

Why are the graphs of some functions not a single line?

Posted: 16 May 2016 05:30 PM PDT

The graphs of some functions are divided into individual lines, such as the graph of the tangent function, secant function, cosecant function, and cotangent function. In the case of tangent and cotangent, the graph looks like several lines that curve deeper the closer x approaches zero, and by mathematical law they will never touch. The same goes for secant and cosecant, only this time the graph of both resembles a layout of multiple parabolas whose vertex has an absolute value of 1. Just like tangent and its reciprocal, the individual lines that make the graph never touch each other. In general, the graph of each of these functions is broken up into individual lines. My question is, why? Why aren't the graphs of these functions (and so many more) united as a single line?

submitted by /u/4w350m3guY
[link] [comments]

How can I calculate the optimal path for a particle through a set of points?

Posted: 16 May 2016 07:41 PM PDT

Given a set of points on a 2D plane, and assuming no friction, how would I go about finding the quickest (or at least a close to optimal) path for a particle through these points assuming that I can change the angle of acceleration as well as the amount of acceleration up to a constant.

For example, say I am flying a rocket and I want to get from point A through point B to point C. I can control which way the thruster is oriented and I can change the thrust value from 0 to k:

- - - - - - - - - - - - - - - B - - - - A - - - - - - - - - - - - - - - - - C - - - - - - - - - - -

The optimal path would be some sort of curve from A to C passing through B. What sort of a curve am I looking for and how could I calculate it? Even some search terms and suggestions would be useful.

submitted by /u/Russian-Assassin
[link] [comments]

How is it that scientists can say that there are more dimensions than our own? What proof is there and where can I find it?

Posted: 16 May 2016 09:28 PM PDT

If we have the technology to image the handful of individual stars as they closely orbit around the black hole at the center of the Milky Way, why hasn't there been a concentrated effort to map all stars on our half of the Milky Way?

Posted: 16 May 2016 04:54 PM PDT

If we can precisely image these stars which are 25k light years away, then shouldn't it be possible to precisely determine the position of all stars within 25k light years?

That would equal half our galaxy.

submitted by /u/woofwoofwoof
[link] [comments]

What is so big about absolute zero?

Posted: 17 May 2016 05:12 AM PDT

What kind of advancement(s) would be made if we were to reach it, which I know can not be done

submitted by /u/720no_scope
[link] [comments]

Why don't grains of salt stick together, if they are formed through ionic bonds?

Posted: 16 May 2016 09:21 AM PDT

Also why does Na and Cl form crystals?

submitted by /u/Mir3al
[link] [comments]

[Physics] Is it possible that the information in the brain survives death? Sean Carroll says we know and understand every particle/force/field that *could* interact with the brain. As a result, if this information were being carried away after death, we could detect it.

Posted: 16 May 2016 10:53 AM PDT

Is it possible that the information on the brain survives death? Sean Carroll claims that although there is a lot of physics we don't understand, we know and understand every particle/force/field that could interact with the brain. As a result, if this information were being carried away after death, we could detect it. He says (in the video below) that if this mystery particle existed you would be able to collide the particles that make up the atoms of the brain and it would generate this mystery particle. He shows rotating a Feynman digram to demonstrate this idea.

Here is a link to a recent article where he mentions it: http://www.npr.org/sections/13.7/2016/05/15/478143589/fear-of-knowing

Here is a link to an older video where he goes into much more detail: https://youtu.be/Vrs-Azp0i3k

If he is right, why isn't this more widely discussed? If he is wrong, I want to understand why. Thanks for sincerely evaluating this.

submitted by /u/BeakOfTheFinch
[link] [comments]

Why are there waves in this water?

Posted: 16 May 2016 08:34 AM PDT

Somehow, the people in this video are riding the very first wave just behind completely still water.

https://youtu.be/GmBWvF6-4DQ?t=155

What could possibly cause this uniform wave pattern that has a beginning?

submitted by /u/TechnoL33T
[link] [comments]

I have a hula-hoop of power cable. If I turn it (fastly) around me, can I induce a current? Does this induce a magnetic field? How much energy could I produce/convert?

Posted: 16 May 2016 08:36 AM PDT

Let's treat this like a physics problem in school, so please assume a spherical power cable in a vacuum.

This question could be really dumb... if so, please explain why. Will it work similar to a dynamo?

submitted by /u/DeutschLeerer
[link] [comments]

What is the Grand Unified Theory?

Posted: 16 May 2016 05:42 PM PDT

Hello all, I am doing a presentation on the Grand Unified Theory and I am wondering if there is any essential information I should include? Also is there any basic analogy I can relate to this theory to give the class I am presenting to a better understanding of the topic? Thanks in advance.

submitted by /u/jonnyfolsom
[link] [comments]

Is there a map of the known universe as it "is" vs what it "was"?

Posted: 16 May 2016 05:47 AM PDT

Every time I see that cool 3D map of the universe, it is prefaced with, "we are looking into the past". While that's cool and all, we do know the location, approximate distance, and approximate direction of travel and speed. Has anyone ever "advanced" the map to where everything is (or should be) positioned today?

submitted by /u/ABrownCoat
[link] [comments]
vào lúc No comments:
Subscribe to: Posts (Atom)