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12:36 AM
@JohnRennie Perhaps it's just my experience, but requiring that students know a lot of information by the end of a relatively short time often means the students have to learn at a faster pace then they'd prefer. I'd find it much easier to teach myself the material if I could read from the textbook at my own pace, such that I can truly understand the material before moving on.
University requires that you've caught up to speed with the material by the time the homework is due, and that you've had enough practice and understanding to be ready for a midterm in a few weeks. That limits how much one can ponder the concepts and gain an intuition.
 
12:49 AM
@SirCumference You have to balance between trying to understand things well and the fact that you will never understand anything the first time you learn it.
 
@DanielSank That's pretty frustrating when the uni ironically makes the learning more difficult. SR left a bad taste in my mouth because of the undue stress and lack of full understanding I associate with it. I should have loved that class, so forgive me if I seem like a grump.
 
1:01 AM
@SirCumference Teaching is hard
 
@SirCumference I think that's a little naive.
University does something you'd never do on your own: it forces you to learn a lot about many topics while your brain is still young enough to absorb information.
I agree that it's frustrating though. I spent my university summers reviewing what I'd learned during the academic year.
I would also say that the more advanced classes tended to go too quickly.
 
@DanielSank Perhaps the most frustrating thing is when tests are curved, so that even a ~75 is still a good score. If you're a professor and your students do not know a quarter of the information, then you are failing at your job at teaching
Sigh, I guess I'm finished venting...
 
 
1 hour later…
2:31 AM
@SirCumference No way, dude.
If students all get 90% on an exam then you're wasting information bandwidth.
 
 
3 hours later…
5:59 AM
A well-formulated exam question requires a higher percentage of the knowledge from the course than its contribution to the final mark. In other words, an exam might contain 10 questions, each of which requires knowledge of 40% of the course's material to complete. In such a case, you might know 90% of the material, but only be able to do 6 of the 10 questions. So a mean score of 75% of an examination in no way indicates that the average student doesn't know a quarter of the material.
2
 
6:21 AM
Hi, I have a couple of questions, anybody there who can help?
 
Possibly. What are your questions?
 
@2physics ask away!
 
Hello John.
 
@JohnRennie Assume an observer is located in a magnetic field (both of the observer and object are stationary with respect to each other, and the magnetic field is constant in time ). Suppose an object turns into the magnetic field. I believe the object should measure an electric field (Maxwell’s equations). The question is that: if the observer feels the caused electric field?@DawoodibnKareem
 
I am wondering if energy eigenstates are always complete given whatever potential?
 
6:30 AM
@2physics Electrodynamics isn't really my area, but I think the answer is no.
 
Another question is that, does the force exerted by the magnetic field (Lorentz law) directly affect the electric charge or it turn into an emf and then affect it?
 
The field is just the field. The static observer and the moving observer simply have different views of it due to their different inertial frames.
 
Why would the object measure an electric field, assuming it has no charge?
 
@DawoodibnKareem Ampere's law says that.
 
I really don't think it does.
Ampere's law requires a current in a loop.
 
6:33 AM
@DawoodibnKareem it doesn't matter if there is a charge or not, as long as we have a moving magnetic field we'll have electric field too.
 
OK, what do you mean by "turns into the magnetic field"? Do you mean the object is turning? Or do you mean it's moving from a place where the field is weaker to a place where the field is stronger?
 
@JohnRennie alright thanks..
 
If it's the latter, then yes, there's an electric field.
 
@DawoodibnKareem no no . I mean it enters into the field
@DawoodibnKareem let me make it clearer. Does a moving magnet create electric field?
 
OK, sure. If the object were charged, it would feel a force because of the changing intensity of the field that it's in. Therefore, even if it's not charged, it's experiencing an electric field.
 
6:37 AM
@2physics that's an interesting question and I must admit it had never occurred to me. In the rest frame of the moving charge there is an electric field present and the force on the charge may well be equal to the charge times this field. I'd have to sit down and crunch some equations to work out if this is true.
 
I simply misunderstood what you meant by "turns". I was thinking a rotating object.
 
It certainly seems a tempting explanation ...
 
@DawoodibnKareem Many people say "Ampere's law" meaning the fourth of Maxwell's equations (i.e. Ampere's law plus the displacement current correction). Not surprising because there is no short, conventional name for the version after Maxwell fixed it.
 
@JohnRennie I think if the answer is yes, then moving an object around a coil which is stationary with respect to a magnet will induce an electric current in it!
@DawoodibnKareem yup. of course
 
@2physics I don't think that's the case. Moving a charge round the coil will obviously induce currents, but moving an uncharged object won't.
 
6:40 AM
I am watching Nima Arkani-Hamed's course on PSI.
didn't know he is the director of the China's coming accelerator
 
@JohnRennie I know. that's why I asked the question. suppose the observer is the charge which is on the coil.
if the entering object causes an electric field which is measurable by the observer(stationary charge for example) then it should have some effect on the observer too.
shouldn't it?
 
@2physics The entering object doesn't cause an electric field.
The field is an electromagnetic field. Some observers will observe a purely magnetic field while some will observe a mixture of magnetic and electric fields.
The fact a moving observer detects an electric field does not mean the field has changed. The field is constant but the different observers have different views of it.
 
@JohnRennie which observers observe what? lol
 
To compare what different observers see we use a Lorentz transformation.
 
the observer which is stationary with respect to the magnetic field. doesn't it measure any electric or EM field?
 
6:51 AM
If you start with a static observer in a purely magnetic field, then to find out what the field looks like for an observer moving with some velocity $v$ you just use a Lorentz transformation.
The result will be a mixture of magnetic and electric fields.
I think you're imagining this is somehow spookier than it is. There is an observer independent description of the electromagnetic field called the four-potential, or equivalently the field strength tensor.
 
Alright then from what that static observer observes we have an electric field added by the entering object to the system. right?
 
Nothing is changing. The EM field doesn't change and what the static observer sees doesn't change.
The fact some other observer is moving doesn't change the field, it just means the moving observer is in effect seeing the EM field from a different perspective.
At the risk of using a slightly dodgy analogy, the EM field is a 4D object living in 4D spacetime.
But we humans live in 3D so we see a 3D view of it.
If you have two observers, one moving and one stationary, then those two observers have different 3D views of the 4D object - kind of as if they're seeing it from different angles.
So the two observers see different things, but they are just seeing the same thing from different angles.
 
"The fact some other observer is moving doesn't change the field" , doen't change the field which static observer measures you mean? but moving observer measures produced EM fields?
:42594438 but according maxwell's equations a moving magnetic field creates electric fields
I'm confused
 
@2physics have a quick look at the Wikipedia article on the field strength tensor - just a quick look, don't worry about the detail.
The field strength tensor, $F$, is a Lorentz covariant description of the electromagnetic field. Note that it has components that look like an electric field, $E$, and components that look lie a magnetic field, $B$.
 
7:07 AM
and?
 
When you change speed you are changing the coordinate system you use to write down this tensor, and as a result the individual entries in the matrix change.
The field strength isn't changing, but your view of it is changing.
There may be a velocity that makes all the $E$ components zero, and for an observer moving at this velocity it will appear as if only a magnetic field is present.
Likewise there may be a velocity that makes all the $B$ components zero, and for an observer moving at this velocity it will appear as if only an electric field is present.
In general both the $E$ and $B$ components will be non-zero and the field appears as a mixture of electric and magnetic fields.
But it's not the field changing. It's the view of the field for the observer that is changing.
If it's any consolation this is pretty advanced stuff - I don't really understand it fully myself!
 
well (although I don't understand the notation! lol)
I still have some problems with this
 
@2physics I'm not surprised. It's flipping hard!
F is a tensor and you need to understand the maths of tensors and coordinate transformations to really get what is going on. That's stuff you won't do until the final years of a physics degree.
 
and according this, you mean I don't interpret maxwell's equations correctly? curl of H equals J and a time varying D. a moving H field can't create a non-zero Curl?
 
When you use Maxwell's equations you use various operators like curl. And these depend on your choice of coordinates because the operators involve $d/dx$, $d/dy$, $d/dz$ and $d/dt$.
 
7:17 AM
yes
 
So you need to have chosen your x, y, z and time axes to do the calculations.
But if you now start moving your axes are different to those of a stationary observer, so all your operators are different.
 
you mean it depends on the frame reference that a moving magnet causes an E fields or not?
 
You need to be a little cautious about statements like a moving magnet causes an E field
 
why?
 
If the magnet is moving relative to you then you are moving relative to the magnet.
So it's the same as a static magnetic field with you moving through it. Yes?
 
7:22 AM
yes. therefore it depends on where we choose our reference frame to be?
 
Yes. We decided a while back that if you're moving through a static magnetic field then you see an electric field.
So does the moving magnet cause an electric field, or does your motion past a static magnet cause an electric field?
And the answer is kind of both and neither
 
well you mean the static observer decides that there wouldn't be any electric field where the moving object enters into the Magnetic field. true?
 
Yes
 
But suppose the moving object is a coil(say a galvanometer). How does the static observer interpret the current that it shows?
 
I have to work now for a bit. Back in an hour or so.
 
7:37 AM
@JohnRennie sure thanks. I'll ask for other opinions on it too. thank you for your help.
 
mornin
 
7:56 AM
hi
 
8:11 AM
"Let i : H → E be an injective continuous linear map with dense image (i.e., the closure of i(H) in E is E itself) that radonifies the canonical Gaussian cylinder set measure γH on H."
Oh no
not radonification
 
 
1 hour later…
9:24 AM
Paper by french people :
"We have studied many applications of functional integration looking for its substantifique moelle."
 
9:34 AM
Anyone ever seen notation such as $\log^{1/5}(x)$? Is this just analogous to $\cos^2(x)=(\cos(x))^2$?
 
Anonymous
@KyleOman Yes
 
Anonymous
and Yes
 
Huh, just when you thought you'd seen it all.
 
That depends on the used convention. $\log_2^2 x$ is frequently used to mean a) $(\log_2 x)^2$ or b) $\log_2 (\log_2 x)$. — Daniel Fischer ♦ Oct 25 '16 at 10:10
 
I've never seen $^2$ used to mean double application
 
9:47 AM
context in the article I'm reading suggests the former
I'd be surprised if it was nested applications
 
context is king
 
unless someone defined that notation explicitly
 
yes, it would be hard to nest a fifth of an application
 
Anonymous
@skullpatrol I'm not sure how the second case applies to $\log^{1/5}(x)$ anyway.
 
you could probably contrive something with a series
 
9:48 AM
Maybe it's $$\frac{1}{\log(\log(\log(\log(\log(x)))))}$$
 
Anonymous
@Slereah XD
 
I seem to remember all sorts of things like that when I studied complex analysis
 
Anonymous
@KyleOman Hi btw. I haven't seen you before
 
moral of the story: never think that you've "seen it all" :-)
 
Anonymous
Good to have an astrophysicist around!
 
9:52 AM
:)
I try not to spend too much time in the chat, and my activity on the site seems to come in bursts.
 
$f^{k}(x)$ is usually the notation for $f(\cdots f(x) \cdots )$ in most of mathematics but in this case it indeed is just exponentiation
 
I am reading up on wieners
(wiener spaces)
 
...it could be interpreted as the reciprocal of the fifth power...
 
Why is it a double wiener
There's a Hilbert space and a Banach space
The Hilbert space is the surprising one since in the example, it's the space of paths with square-integrable velocities
But those are of measure 0 in path integrals, I think?
"If H (and E) are infinite dimensional, then the image of H has measure zero: γ(i(H)) = 0. This fact is a consequence of Kolmogorov's zero–one law."
Ah yes
there we go
what's the ween for Klein Gordon
And me at work without my Grimm and Hella Jeff
 
10:54 AM
"Eucleadian Quantum Field Theory"
what is it with people being unable to spell Euclidian
 
I didn't know Euclid had worked on QFT.
 
He was ahead of his time
 
11:18 AM
@Slereah what is it with people being unable to spell 'hermitian'?
 
All the -ian words get misspelt
 
@Slereah is there a function $f:(0,\infty)\to(0,\infty)$ such that (i) $f(x)\to\infty$ as $x\to\infty$, (ii) for every $n$ and $C$, there exists an $x_0$ such that $f(x)<\log^{\circ n}(x)$ for all $x>x_0$ (where $\log^{\circ n}$ is the composition power of $\log$, i.e. $\log$ applied $n$ times) but nevertheless (iii) that bound is saturated, i.e. there is no better way to express how slowly $f(x)$ goes to infinity?
 
@Slereah Laplaician - a French technique for cooking fish
2
 
Anonymous
11:36 AM
@EmilioPisanty Interesting question. Reminds me of the inverse Ackermann function...
 
Anonymous
I haven't checked if it matches all your conditions though
 
12:01 PM
@EmilioPisanty sounds unlikely
Unless the sequence $\log^{\circ n}(x)$ converges for $n$ to something that isn't $0$
 
12:22 PM
@JohnRennie, Hi John what I meant is: most photons are going to hit the external layer of nuclei and be scattered, sogiving one billionth of their energy. I tat is wrong and photons of that order can get through the body, then energy is amplified, since the electrif field acts in all directions. If you have one electron and another charge at r you give k energy, if ther are 1000 electrons around at are you are giving 1000 k, is that right?
 
The scattering of light isn't usually very strong in insulators (metals are a different matter). It certainly isn't true that the light will be scattered off the first layer of nuclei it hits.
In fact scattering of light by the nuclei themselves is negligible because the nuclei are too heavy. It's like you trying to transfer energy to a battleship by pushing it.
You won't be able to transfer any energy because you can move the battleship.
 
also there aren't a lot of energy levels in nuclei that are separated by a few eV
 
Push on something lighter, like a small car, and you can transfer energy to it very efficiently.
 
unless you're blasting gamma rays at it
 
@Slereah no. A few eV? What have you been smoking? :-)
A few MeV possibly ...
@user157860 I have to leave for a meeting in 10 minutes. I'll be around later on today if you want to pick this up.
 
12:33 PM
yes, hence what I said :p
I'm trying to find stuff on rigorous non-Euclidian path integrals
But it's the worst of all
It's both very handwavy but also very formal
Apparently miss DeWitt did write a paper on the topic
 
Hi guys. Just want to inform you that I introduced the "ergodicity" tag. Help in tagging old questions is much appreciated, just maybe let's not do it all at one otherwise we will fill the board with questions about ergodicity. Cheers!
*all at once
 
@JohnRennie, how deep can infrared light go in a block of iron/metal? won't many more photons be stopped by nuclei than electrons? Of course I didn't expect much energy to be transferred, that's why I said in my comment that 100% transfer is not by far possible.
 
it will be stopped by electrons
 
@Slereah, even the photons stopped by electrons will give a fraction less tha one millionth of their energy, so , how much of a thermal radiation at 10^12 Hz will be actually transferred to a block of metal?
 
12:49 PM
@user157860 Look up the absorption coefficient of the material
 
Jan 22 at 7:58, by Secret
Still checking the reason for the 1st though
Using a debugging technique akin to squeezed states, finally narrowed down to the possible source of the heisenbug as possible competition to rename the file temp.xyz as multiple jobs finishes roughly at the same time, result in misplaced entries and missing entries
temp.xyz is now renamed to something unqiue to each job to avoid competition. Whether this resolves the heisenbug remains to be seen
Fun fact: Bugs in my programs tend to reccur even if they are heisenbug, thus they are almost guarenteed to be able to nail down and squashed
 
1:04 PM
Hey @0celo7
 
Hola
 
Apparently miss Cécile Dewitt-Morette found some way to define path integrals in the non-euclidian regime
I am giving it a looksie
 
\begin{align}
\mathcal{Z} &= \mathcal{N} \int \Pi_i dx_i \exp [ i \sum_i L_i \delta t ] \\
&= \mathcal{N} \int \Pi_i dx_i dp_i \exp [ i \sum_i (p_i \dot{x}_i - H(x,p)) \delta t ] \\
&= \mathcal{N} \int \Pi_i dx_i dp_i \exp [ - i \sum_i H(x,p) \delta t ] \exp [ i \sum_i p_i (x_i - x_{i+1})] \\
&= \mathcal{N} \int \Pi_i dx_i \{ \exp [ - i \sum_i H(x,p) \delta t ] \exp[ - i \sum_i p_i x_{x+1} ] \} \int dp_i \exp [ i \sum_i p_i x_i ] \\
&= \mathcal{N} \int \Pi_i dx_i \{ \exp [ - i H(x,\partial_x) \delta t_i ] \exp[ - i \sum_i p_i x_{x+1} ] \} \int dp_i <p_i |x_i > \\
I think that's how you end up with Heisenberg states from the path integral, at some point defining $<p|x_i> \approx e^{ip_i x_i}$
 
@Slereah huh
 
Well it's best to have something
because if a spacetime isn't static, there's no Euclidian path integral defined
Also the Wiener measure (heheheh) involves a Hilbert space of the configuration space
I'm wondering if it's related to the canonical quantization Hilbert space
 
1:24 PM
temperature range is 35 degrees today
no matter what I wear, I will be screwed
 
Wear a space suit with integrated AC
 
1:50 PM
DeWitt defined the Fourier transform of a random Banach space
For a measure of $X'$ $\lambda$, $$\mathscr F [\lambda(x')] = \int_X e^{-i\langle x', x \rangle} d\lambda(x)$$
that paper isn't a fun read
 
Hi @Secret. Needed your help to decide which OC kit I should buy.
 
...wouldn't it be better to ping him in the chem room?
 
@skullpatrol he isn't online there.
That's why I asked him here.
 
The "@" still works there.
The message will show up in his inbox.
 
2:05 PM
??
 
@Secret Please visit periodic table.
 
@Secret “heisenbug “ is a great word. I may have to steal that
 
@Semiclassical It's a known term in the computing commmunity
In computer programming jargon, a heisenbug is a software bug that seems to disappear or alter its behavior when one attempts to study it. The term is a pun on the name of Werner Heisenberg, the physicist who first asserted the observer effect of quantum mechanics, which states that the act of observing a system inevitably alters its state. In electronics the traditional term is probe effect, where attaching a test probe to a device changes its behavior. Similar terms, such as bohrbug, mandelbug, hindenbug, and schrödinbug (see the section on related terms) have been occasionally proposed for other...
 
Mandelbug?
:-D
 
2:37 PM
I want to get a Switch
 
you're falling for the console trap
 
blade?
 
yo @Semiclassical whatcha make of these "Stokes" lines?
I'm doing $\int_{-\infty e^{i\pi/8}}^{\infty e^{i\pi/8}} e^{ik\left[\frac14 t^4-\frac32 t^2+(\Omega+i u)t\right]} \mathrm dt$
those are the lines where the real parts of the exponent at two different saddle-points coincide
the ones on the real axis are the three-way things that you'd expect
but wtf's up with that six-way non-120°-angle intersection on the imaginary axis?
though I guess you could see it as two three-way-120° ones overlaid on top of each other?
that's what the saddles look like as you do a circle around one of the six-way ones
but at the intersection itself there isn't a coalescence
it's more of a this kinda thing
what really weirds me out is that there is one, (but only one) of those 1/6th slivers where you only need one saddle on the contour
 
2:55 PM
$$\int_{\mathrm Z_0} \mathcal D_{s, Q_0} z \cdot \exp(- \frac{\pi}{s} Q_0(z)) \varphi(x_0 \cdot \Sigma (T,z))$$
Jesus
 
I mean, what's up with that?
 
It is apparently the solution to the generalized Schroedinger equation $$\frac{\partial \Psi}{\partial T} = \frac{s}{4\pi} h^{\alpha \beta} \mathcal L_{X(\alpha)}\mathcal L_{X(\beta)} \Psi + \mathcal L_{Y} \Psi$$
 
@Slereah lol
 
though I think this is all for point particles
but I'm not 100% sure
 
3:13 PM
Hmmmmm.
So, how probable or improbable is the existence of period table elements past Oganesson anyway?
 
@Slereah the stability of Minkowski is actually horrific
 
@Slereah. What properites besides being heavy does Unbibium hypothetically have?
 
@0celo7 is it not actually stable
 
@Slereah the proof is so technical...
 
user228700
@EmilioPisanty What's going on here...
 
3:26 PM
@KaumudiH the magic of saddle points ;-)
 
user228700
I... don't see.
 
Kind of makes a lot of sense why you'd want to re-formulate that path integral above as inner products of vectors the way it's done, kind of makes sense why you'd define the path integral in terms of exponenetials and phases
Still madness
 
My favorite thing about saddles is that there's a surface called a monkey saddle
because it is the theoretically ideal surface for a monkey to sit on since it has a space for the tail
Well the real problem about path integrals is that they're not really integrals
at least not in the common math sense
There's no measure that give you the QM path integral
so you have to define weird generalizations like pseudomeasures and integrators
 
The saddlepoint approximation method, initially proposed by Daniels (1954) is a specific example of the mathematical saddlepoint technique applied to statistics. It provides a highly accurate approximation formula for any PDF or probability mass function of a distribution, based on the moment generating function. There is also a formula for the CDF of the distribution, proposed by Lugannani and Rice (1980). == Definition == If the moment generating function of a distribution is written as M ( t ) {\displaystyle M(t)} and t...
Wikipedia is a bit light on the details =P
 
user228700
@EmilioPisanty Cool, thanks :-)
 
3:30 PM
Hmmmmmm.
 
saddles are the things you sit on
 
So, question: is there a better magnet to contain antimatter than neodymium magnets?
 
basically, you have some function $F(k) = \int_C f(z) e^{k g(z)} \mathrm dz$ for some complex contour $C$, and you care about the behaviour of the function as $k$ is large
 
Measure theory was formulated in a way that completely missed probability theory, now we see measure theory missing path integrals, the math is wrong not path integrals :p
 
so because the exponent does all the heavy lifting, you deform your contour so it goes over the hills of $e^{g(z)}$ and you keep the contributions from the top only
and that tends to work really well
the catch is finding the appropriate contour that goes from where you need to start to where you want to go and which doesn't "go sideways" as it climbs up or down those hills
that's the thicker black lines
as the animation progresses, the configuration of $g(z)= g(z;\mathrm{parameters})$ changes, so the choice of contours changes
... in messy ways that I don't fully understand
 
3:34 PM
@Slereah the first 50 pages of this book is just $S^2$
 
How do you measure a function in a function space, maybe measuring is not the true essence of integration, idk
 
@KaumudiH ah, this is much better
In mathematics, the method of steepest descent or stationary-phase method or saddle-point method is an extension of Laplace's method for approximating an integral, where one deforms a contour integral in the complex plane to pass near a stationary point (saddle point), in roughly the direction of steepest descent or stationary phase. The saddle-point approximation is used with integrals in the complex plane, whereas Laplace’s method is used with real integrals. The integral to be estimated is often of the form ∫ C ...
 
denisty of functions in this region
 
@0celo7 $S^2$ isn't even a spacetime
 
@Slereah when you do a double null foliation you end up with spheres
 
3:38 PM
true
 
Hnmmmm.
So, what applications do room-temperature superconductors have outside of computing, railguns and the like?
Because I wanted to know: could they help in antimatter containment?
 
I am coming down with a cold
I can feel my throat getting sore
RIP
Is there even a theorem proving that Wick rotation gives the same thing for path integrals
It's probably in Gromm and Jazzy Jeff
 
ok mr christo how the fuck do you estimate $diam(S)/r$ from above using the "Bonnet formula"
oh
he means the Bonnet-Myers formula
fucking hell
sad it took me so long to figure that one out...
 
3:54 PM
Do the musical isomorphisms have a name
Should I call them sharp and flat or something
 
user228700
I have a quick question! Oh, I even wrote to my favorite advice podcast about the same, so here is the e-mail I sent them:
 
user228700
> "Over the years, I have come to understand that I am most productive in the wee hours of the morning, starting at 4:00 AM. I have also found out, through trial and error, that I function best when I have had at least 7 hours of sleep the previous night. Now, these two facts combined, has left me going to bed as early as 8:30 PM!"
 
user228700
> "Surely you understand why this has planted in me, a new concern for my social life, which is already astonishingly poor for a college student. Any advice is certain to be of great help to me."
 
user228700
Does anybody here have any advice they'd like to provide (please)?
 
user228700
...nothing? Really? Guys.
 
4:04 PM
@KaumudiH this is natural selection at work, I’m afraid
 
user228700
Excuse me, while I grab some salve for that burn.
 
I have no constructive comments to make on social lifes, unfortunately. Maybe that says I'm a useless fuckhead who reads math books and types vigorously into his keyboard sitting in his mother's basement, and so be it
 
Hmmmmm.
I had an idea.
 
user228700
@BalarkaSen I always thought you were locked away in an attic. Basement, nice.
 
How impractical is an antimatter version of a Bussard Ramjet?
 
4:07 PM
I’m amazed his parents let him in the house.
 
please no harry potter bullshit
 
@FutureHistorian how much antimatter do you expect is in space
(hint it's zero)
Hence not at all practical
 
user228700
@BalarkaSen You mean a cupboard, but sure.
 
@Slereah. I mean like........this:
Step 1. Use antimatter as fuel.
 
hypothesis: harry potter actually developed a paranoid schizophrenia eternally locked away in his attic by his abusive uncle and aunt and imagined all of the events in Harry Potter 1-7 in his mind
That's the right story
 
4:09 PM
Step 2: Scoop hydrogen to serve as propellant to use when mixing with the fuel.
 
That's how it goes
oh yeah cupboard not attic. rip
 
Step 3: Activate magnetic scoop once you are ready to slow down in your destination + collect propellant.
Step 4: Profit???
@Slereah? Basically, picture antimatter as the fuel and regular hydrogen as propellant.
 
@BalarkaSen do you watch Molyneux?
 
user228700
@BalarkaSen Regardless, it's a detailed and interested. And now, I am going to quit glorifying H.P again, before I piss you off :-P
 
That’s his theory on Harry Potter and Star Wars
 
4:11 PM
Which one?
 
@0celo7 Oh really? I have never heard of him
 
@KaumudiH does Balarka dislike HP?
 
Because if we are talking game developer Molyneux........well, he is terrible. Political Molyneux.......also terrible.
 
@BalarkaSen you wouldn’t like him
 
I think HP is ok
 
user228700
4:12 PM
Feb 8 '17 at 18:06, by Balarka Sen
HP (both books and movies) is a good fantasy fiction series. But I think there are better fantasy fictions :)
 
I don't mind glorification. It's just a harmless story
 
@FutureHistorian not an argument
 
Oh.
@0celo7? So, using antimatter as fuel for a Bussard Ramjet collecting normal hydrogen as propellant = ???????
 
user228700
GAH, it's almost 10, and I'm still up, and I have exams on Monday, and AGH.
 
That’s a mostly insane question.
 
user228700
4:13 PM
Bye :-(
 
Basically, instead of using a Bussard Ramjet for a fusion rocket........
We use it for an antimatter rocket.
So, basically, picture a Bussard Ramjet but with an antimatter engine.
Could it work?
Or still fail as the regular Bussard Ramjet?
 
Anonymous
4:28 PM
@KaumudiH I always find myself least productive if I wake up early (like 4 am) even if I have slept for 6-7 hours, before that.
 
Anonymous
I'm probably hard-wired to be a night owl
 
Anonymous
@BalarkaSen Social life is extremely overrated anyway :P
 
@JohnRennie : Poisson - a French technique for undercooking fish...
 
vzn
~275 refs to susskind in here. just bought his book on QM. via reddit physics ran across this new video espousing universe-as-simulation. any reactions?
 
4:54 PM
Susskind is great
 
vzn
@bolbteppa yeah! what about 't hooft? (who espouses similar ideas!) heres the reddit comments thread, maybe someone can add some intelligence reddit.com/r/Physics/comments/7tzbyo/…
 
Adding intelligence to Reddit seems like a daunting task :P
 
@Qmechanic all of French cuisine consists of ways to undercook food.
 
He's great too, you should read this staff.science.uu.nl/~gadda001/goodtheorist/index.html
 
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