The h Bar

danielunderwood

00:01

huh

enumaris

00:22

I should review the attention portions of the coursera course again...

seems like attention is the future

better not get stuck with these clunky LSTMs and GRUs

danielunderwood

00:58

Was that in the Ng course? I haven't even heard of attention so far

Sir Cumference

howdy

peterh

01:44

@danielunderwood Boston Dynamics uses probably a lot of AI, or at least some advanced data processing for robot control

@danielunderwood They use probably no AI in the realtime control, but they use a lot of AI to develop the control mechanism.

peterh

02:16

@SirCumference The unemployment rate is < 5% in most developed countries, and they are young talents coming from the University. I don't believe that there wouldn't be jobs. But, what I see on them, that their skills are far from the level what I would expect from a BSc/MSc

Sir Cumference

02:32

@peterh Notice the quotation marks :P

GodotMisogi

06:08

I'm currently attending a presentation on "Darkly Charge Dark Matter" by Lisa Randall

Avantgarde

Can someone recommend a good pdf (and possibly djvu too) viewer for Mac?

(Free)

John Rennie

07:17

@Avantgarde isn't Acrobat Reader available for OSX?

For djvu I use DJView.

Physics Meta

07:42

0

Q: How to respond to this user's "geopotential waffle" comments and/or best edit my question?

I'm at a loss how to handle the comments below my question. They seem accusatory but not valid or thought out from a physics perspective. this is the same (ridiculous) question posted in several forms by two members on three SE sites. It's time to bury this nonsense question. It's not e...

discussion

Avantgarde

08:00

@JohnRennie I don't think so. Or it's not free, I guess.

@JohnRennie Same.

I liked sumatrapdf but it works only in windows.

John Rennie

@Avantgarde yes it is

@Avantgarde and DJView is available for OSX as well

Avantgarde

@JohnRennie Thanks, let me see. I use Djview already.

uhoh

12:00

@JohnRennie you've helped me a few times with physics insight with just a few sentences. Do you see anything unclear or unphysical in Has this unusual orbital mechanical problem been addressed, or given a specific name? or the linked meta question

John Rennie

@uhoh I saw the question but I wasn't sure what you were getting at. Presumably your ball on a stick interacts in some way with the tidal forces, but what role does the quadrupole play?

uhoh

To raise or lower an orbit, you need some component of the force to be in the direction of motion. The Oblateness (J2) of the Earth does that, but it integrates to zero over one orbit.

When the orbiter can change its quadrupole moment as well, there may be a way to modulate that so that the tangential accelerations no longer integrate to zero over one orbit.

Akash. B

@JohnRennie are you free now?

uhoh

I'm not so much trying to "get at" something as to try to find out if this problem has been addressed or solved, or perhaps how to solve it myself.

Akash. B

@uhoh hi

uhoh

12:05

The Moon and tidal forces are not necessarily the best way to look at this problem, the mechanism is more general.

John Rennie

I guess if you can make the force no longer $r^{_2}$ then the orbit can spiral in or out. If both objects have a significant quadrupole that might modify the distance dependence.

@Akash.B hi, I'm around for a bit ...

uhoh

yes I think that is possible, which is why I'm a proponent of this question. For some reason I can not understand, it seems unpopular.

Akash. B

@JohnRennie "the higgs boson is particle which gives an object its mass" is this statement true?

John Rennie

@Akash.B no. The Higgs field gives mass to elementary particles. The Higgs boson, as observed at the LHC a few years back, is just a side effect of the Higgs field.

Akash. B

@JohnRennie I have an another question too

John Rennie

12:10

@uhoh I'm not sure I'd say it's unpopular just because StephenG didn't like it. My problem with it is that it wasn't clear what the point of the question was.

@Akash.B yes?

Akash. B

@JohnRennie can a violet light obtained from the dispersion of white light dispersed into any other colours?

John Rennie

@uhoh I see the question has now been closed as unclear what you're asking so I guess I'm not the only one who feels that way.

@Akash.B are you asking if we use a prism to split light, then select the violet light can that violet light be split onto other colours?

Akash. B

@JohnRennie yeah

John Rennie

What a prism does is separate light based on its wavelength. Red light with a wavelength of 70nm is at one end of the spectrum while violet light with a wavelength of 40nm is at the other end.

Akash. B

okay

John Rennie

12:14

So if you select the violet light you have light with some range of wavelengths around 40nm.

e.g. your selection might include wavelengths 38-42nm.

Akash. B

okay

John Rennie

If you pass it through another prism it would spread the light again, but you're never going to get any new wavelengths that weren't present before it went through the prism.

So for example you'll never get red light coming out.

Akash. B

??

uhoh

@JohnRennie I will work on that then, thanks.

Akash. B

@JohnRennie would anything happen if we pass a red light and a white light at same time?

John Rennie

12:22

@Akash.B a prism bends light by an angle that depends on the wavelength of the light. So red light will be bent by the same angle whether it's just red light or red light present as a component of white light.

Anonymous

13:06

Holla @Jim

Jim

@Blue Hello

Anonymous

@Jim It's rare to see you on SE these days. I guess we last spoke during your AMA. Got busy? :)

think__tech

13:36

Is there an official solutions manual for \Vibration and Waves by A.P. French ?

Physics Meta

14:54

0

Q: Deleting an Answer

An answer of mine was recently deleted because it was decided AFTER my answer was posted and accepted that the question was off topic. I thought putting a question on hold simply prevented any further answers from being posted. By why delete an answer already accepted before the on hold decision ...

discussion

enumaris

16:57

whewie

enumaris

17:23

interesting start up contacted me yesterday

Beyond Limits...apparently they are doing something in the A.I. + space exploration space...not sure what exactly though...

danielunderwood

17:39

Tell them you want to go to space

ACuriousMind

@enumaris Yes, lets send AI to space so we can also mess up other planets by proxy. Make them self-replicating as a bonus - that never went wrong in any SciFi story...

enumaris

XD

For when working on the grey goo here on Earth isn't enough

some good news this week :')

well, good news in terms of job opportunties...

a lot of bad news in other areas...but we won't dwell on that...

danielunderwood

Nice!

enumaris

17:54

Amazon robotics has contacted me

dunno what they do tho

danielunderwood

I didn't even know amazon robotics was a thing

Maybe robots for their warehouses and delivery drones?

John Rennie

Amazon Robotics

Amazon Robotics, formerly Kiva Systems, is a Massachusetts-based company that manufactures mobile robotic fulfillment systems. It is a subsidiary company of Amazon.com and its automated storage and retrieval systems were previously used by companies including: The Gap, Walgreens, Staples, Gilt Groupe, Office Depot, Crate & Barrel, and Saks 5th Avenue. After those contracts ran out, Amazon did not renew them and Kiva's assets now work only for Amazon's warehouses. == History == After working on the business process team at Webvan, a failed online grocery delivery business, Mick Mountz concluded...

danielunderwood

Hmmm evidently MA is the place for robotics?

djsmiley2k

Sooooooooo

can i make diamonds with peanut butter?

honest question, because I like doing interesting things with my daughter, and while i can't imagine it's real, it looks awesome >_<

Sir Cumference

Does theory of relatively absolutely flawless?

John Rennie

18:06

@djsmiley2k Yes but you have to dissolve it in molten iron (at least I think that's how diamonds are grown synthetically) which is probably not an ideal home experiment.

djsmiley2k

Awww what :/

John Rennie

I guess you're thinking of this work

djsmiley2k

yah

bolbteppa

Don't boo, vote

djsmiley2k

well, there was some 'educational' videos my wife saw on facebook

One had this

gfycat.com/circularlikablefawn

enumaris

18:22

ah so Amazon Robotics is actually a subsidiary, not a department of Amazon

hmmm

if I click "yes" to a google calendar invite does it send an email letting them know? If so, does it send a separate email every time I click "yes"? o.O

I didn't get like a confirmation pop up when I clicked yes

but I don't want to click yes 20 times and flood that person's email lol

Avantgarde

@JohnRennie Acrobat works fine. The search algorithm is nice too. But I need one more thing. When I search a keyword, I have to press enter each time I want to go to the next search item. Is there a place where I can see all the searched items collected in a list format, marked by page numbers?

This happens in the other viewer I had. I'm not sure if Acrobat has that feature too. I can't seem to find it.

@JohnRennie Chole chicken? That's an odd combo. How was it?

Never mind, I found it. But it's not very efficient, because the search list is in a different window. I have to switch back and forth between the search window and the pdf window. Is there a way to circumvent this?

That's why I don't really like Adobe reader. It's too heavy. A simple, light, no-nonsense reader is what I need.

enumaris

18:44

this transformer network is interesting stuff

Avantgarde

18:59

Never mind, I solved (almost) my problems.

enumaris

19:24

Have all the Americans here gone and voted? Voting is a civic duty! Go vote plz! :D

3

Captain Bohemian

vote what?

enumaris

Vote in the midterm elections. :)

Captain Bohemian

election of what?

bolbteppa

Against the Republicans

enumaris

Election of senators, congressmen, governors, other local officials and also for propositions and stuff

I'm avoiding telling people who or what to vote for, only that voting is important :D

bolbteppa

19:29

boo

Captain Bohemian

I am not an American, but we will also have an political election this month.

danielunderwood

@enumaris just got my sticker!

Sir Cumference

20:41

@enumaris Ironically don't have the time since I'm worrying about midterms :/

enumaris

@danielunderwood nice nice :D

@SirCumference awww, doesn't your uni give you some time off?

Sir Cumference

best joke I've heard all year

in seriousness, I definitely don't have the time to research any of the candidates

enumaris

you don't have to vote in every category

you should be able to just vote for the ones you know

Sir Cumference

which is none, and rushing my research would basically lead to uninformed voting

Semiclassical

@bolbteppa that's my frame of mind in at least one race: I'm not voting for the democratic candidate (whose personal judgment I've lost a lot of confidence in) but I am voting against the republican candidate

enumaris

20:45

@SirCumference don't need to be an expert to vote

just know their general policies

Semiclassical

and since there's only one practical way to vote against someone in a two-party system...

enumaris

much better than the blind party voting by a majority of voters anyways

@Semiclassical unfortunately I know of no initiatives in congress for changing the voting system away from first past the post voting.

Semiclassical

in general tho I feel like the best description of the US two-party system is:
"The best lack all conviction, while the worst // Are full of passionate intensity"

enumaris

21:11

wow, comparing named entities is taking a long time...

just a few million keys to loop through...

Jake Rose

21:43

m.imgur.com/1i6EhHt Posted this in the maths chat but nobody responded so

I tried differentiating twice but doing this to g wrt x just gives 0?

David Z

21:58

@JakeRose Even at $x = \xi$?

(I can't stay to follow up, just figured I'd interject that point)

Loong

@DavidZ Would you like this question? chemistry.stackexchange.com/q/103883/7951

peterh

@enumaris Vote for closure!

enumaris

22:38

closure of what?

David Z

@Loong I guess it is on topic for us, though it isn't a particularly good question. It's not researched, and I bet there would be multiple duplicates.

vzn

22:59

Physicists might have created quantum entanglement in bacteria / TNW

rob

23:11

@vzn The technical article.

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