Search found 436 matches

by lgw
Sat Aug 16, 2014 5:55 pm UTC
Forum: Science
Topic: Does acceleration increase rest mass?
Replies: 29
Views: 6518

Re: Does acceleration increase rest mass?

Well, one thing to clear up: there's an often-taught, always-wrong notion that mass increases at relativistic velocities, as a misunderstanding of the momentum increase (as seen from a frame in which the object is moving close to c) and misguided attempt to explain why you can't reach the speed of l...
by lgw
Sat Aug 16, 2014 12:45 am UTC
Forum: Science
Topic: Dark Matter
Replies: 27
Views: 6428

Re: Dark Matter

I've been amusing myself with the idea that there are 10 or 20 kinds of dark matter, each fundamentally different in some way. For example, matter with analogs to the proton and electron, but bound so tightly that at present energy levels, or even at the energy levels present when the universe was 1...
by lgw
Thu Jul 31, 2014 2:03 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1224: "Council of 300"
Replies: 7
Views: 6039

Re: 1224: "Council of 300"

Just because it's remotely possible that someone here hasn't seen the explanation for why this happens (but mostly because Numberphile is made of win and awesome).
by lgw
Thu Jul 31, 2014 12:50 am UTC
Forum: Coding
Topic: Help Wanted
Replies: 36
Views: 81776

Re: Help Wanted

My team within Amazon EC2 needs developers. If working on this product appeals, read on! My Spot cluster is faster than your supercomputer. :D Here's an example help-wanted ad for a position on the team, but the key bit is this. Developers on this team need a sound understanding of the fundamentals ...
by lgw
Thu Mar 27, 2014 11:54 pm UTC
Forum: General
Topic: Mod Madness 2014 : The Announcement
Replies: 542
Views: 126265

Re: Mod Madness 2014 : The Announcement

This is such stupid childish nonsense. Not sure if I'm coming back after it's over, so pre-emptive farewells!
by lgw
Thu Mar 27, 2014 11:46 pm UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9979
Views: 1979964

Re: Coding: Fleeting Thoughts

EvanED wrote:
Yakk wrote:"%d"_printf( x );
I honestly feel like this is a candidate for a "Most Pointlessly Obtuse Use of Language Syntax" award.


How is that I don't even?
by lgw
Thu Mar 27, 2014 12:01 am UTC
Forum: Coding
Topic: Funniest/Most Annoying Code Comments
Replies: 662
Views: 142700

Re: Funniest/Most Annoying Code Comments

One of my own, from a while back.

Code: Select all

// Using XML here is like swatting flies with a sledgehammer dropped from orbit.
// But, hey, they want to pay me to build the rocket ship and I need the money,
// so here's some XML!
by lgw
Wed Mar 26, 2014 11:46 pm UTC
Forum: General
Topic: How to know you're truly old.
Replies: 156
Views: 59406

Re: How to know you're truly old.

Today I saw a clever political ad by a senatorial candidate ("I grew up on a farm castrating hogs, so I know how to cut pork!"), then realized I was older than her. Older than the distinguished-looking potential Senator. Eesh. :shock:
by lgw
Wed Mar 26, 2014 8:03 pm UTC
Forum: News & Articles
Topic: Iran is building a Fake Aircraft Carrier
Replies: 50
Views: 12582

Re: ایران is building a Fake Aircraft Carrier

But then, no low-tech opposing force pilot is going to get within visible range of a US carrier in any case, A submarine would, and results from training excercises suggest it could be quite succesful if it manages to evade the anti-submarine part of the carrier battle group. It's happened at least...
by lgw
Wed Mar 26, 2014 12:47 am UTC
Forum: Science
Topic: Rate of Entropy
Replies: 18
Views: 4505

Re: Rate of Entropy

We don't do it to emulate anything, and there's really nothing *to* do well. We're not doing it to accomplish some goal, we're doing it so we can have a bit of fun from time to time. But don't you worry your pretty little head about it, we'll probably just go ahead and ban you for the duration, sin...
by lgw
Tue Mar 25, 2014 7:34 pm UTC
Forum: Science
Topic: Rate of Entropy
Replies: 18
Views: 4505

Re: Rate of Entropy

*wordfilters are childish, guys. The joke was "funny once", many years ago . Now it's just sad. You're probably gonna want to take a wee break from the forums this weekend into next week, then. Sigh. It's bad enough when you decide to emulate the chans in their heyday, but you don't do it...
by lgw
Tue Mar 25, 2014 5:35 pm UTC
Forum: News & Articles
Topic: Iran is building a Fake Aircraft Carrier
Replies: 50
Views: 12582

Re: ایران is building a Fake Aircraft Carrier

Except the Th is so clearly enunciated that I'm considering banning anyone who insists it's "erf" on the grounds they are racist shitheads. . And nothing of value would be lost. Hey now! Erf is one of my favorite webcomics! It's worth noting that the pictures above show a carrier battle g...
by lgw
Mon Mar 24, 2014 6:05 pm UTC
Forum: Science
Topic: Rate of Entropy
Replies: 18
Views: 4505

Re: Rate of Entropy

To emphasize gmalivuk's point: the state of a system just sort of wanders chaotically (informally "at random", whether or not it's truly so it will look plenty random). A given ordered state is no more or lesss* likely than a given disordered state, it's just there are few of the former an...
by lgw
Fri Mar 21, 2014 7:10 pm UTC
Forum: Science
Topic: Planck lengths and length dilation
Replies: 11
Views: 4137

Re: Planck lengths and length dilation

... Also note that, as the first link mentions, we can actually test this possibility to some extent by looking at gamma rays that have traveled so far across the universe that the tiny artifacts of discretized space add up to significantly affect their travel time. That is very, very cool. Wow, wh...
by lgw
Tue Mar 18, 2014 7:57 pm UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9979
Views: 1979964

Re: Coding: Fleeting Thoughts

Speaking of petty things: it seems like you dislike copypasta and boilerplate, so why are you using Java? We use Java at work. You can change that. :P (I actually changed jobs about a year ago, partly because Java is so wretched to work with. Not sure I'd refuse a future Java job, but the word does...
by lgw
Tue Mar 18, 2014 7:52 pm UTC
Forum: Coding
Topic: Suggest an open-source C/C++ IDE
Replies: 22
Views: 7809

Re: Suggest an open-source C/C++ IDE

So qtcreator consumes all 32G in the system while trying to parse the project and eventually gets killed when the OS runs out of swap. It didn't come close to finishing parsing, either. It didn't even make it 1/4 of the way. The winner so far is something called Codelite, which honestly could use m...
by lgw
Tue Mar 18, 2014 5:32 pm UTC
Forum: Science
Topic: Question about Planck Units
Replies: 13
Views: 3476

Re: Question about Planck Units

... Well, the Planck temperature might be the highest possible temperature (give or take a simple numerical factor). Similarly, the Planck mass may be an upper bound for the mass of a fundamental particle, although it's way heavier than any of the fundamental particles we know about. :) OTOH, the c...
by lgw
Tue Mar 18, 2014 5:17 pm UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9979
Views: 1979964

Re: Coding: Fleeting Thoughts

I have a Java class that extends some other class. I want to override some methods only some of the time. The dumb way is this: public methodToSometimesOverride( ... ) { if ( condition ) { //do stuff } else { super.methodToSometimesOverride( ... ); } Which is reasonable, but I'd have to copy-paste ...
by lgw
Tue Mar 18, 2014 12:38 am UTC
Forum: Coding
Topic: Suggest an open-source C/C++ IDE
Replies: 22
Views: 7809

Re: Suggest an open-source C/C++ IDE

I hear good things about QT Creator - it might not have your complete checklist, I'm not sure, but it's a full-featured IDE. Anyone have some first-hand QT Creator experience to share?
by lgw
Tue Mar 18, 2014 12:25 am UTC
Forum: Science
Topic: Question about Planck Units
Replies: 13
Views: 3476

Re: Question about Planck Units

It's somewhat coincidental. I would argue that it's not at all coincidental. The principle of dimensional analysis says that, if you can only form one (time, length, mass, etc.)-scale from the relevant constants of your system, that scale should be roughly the correct answer. What constants should ...
by lgw
Mon Mar 17, 2014 8:58 pm UTC
Forum: Science
Topic: Question about Planck Units
Replies: 13
Views: 3476

Re: Question about Planck Units

Why is it that this length results when setting certain fundamental constants to 1, though? Given that all five of the constants have length in their dimensions, there doesn't seem to be any obvious reason that that would be the case. It's somewhat coincidental. The formula for the "minimum si...
by lgw
Mon Mar 17, 2014 5:39 pm UTC
Forum: Science
Topic: Question about Planck Units
Replies: 13
Views: 3476

Re: Question about Planck Units

The Plank length is special because it's the smallest length (or perhaps the most precise possible measurement of length - the two ideas are somewhat interchangeable) possible in the universe. This stems from the fact that as the wavelength (size) of a particle gets smaller, its energy (and therefor...
by lgw
Sat Mar 15, 2014 12:03 am UTC
Forum: Science
Topic: Planck lengths and length dilation
Replies: 11
Views: 4137

Re: Planck lengths and length dilation

You can't really have the treatment of momentum and spacetime be tooo different, since they're conjugate variables in quantum theory. Likewise you couldn't really have 'energy' or 'momentum' be more fundamental, since those are just components of a 4-vector. We can't be sure how weird the next theo...
by lgw
Fri Mar 14, 2014 7:46 pm UTC
Forum: Science
Topic: Gravitational mass of an electron?
Replies: 35
Views: 11818

Re: Gravitational mass of an electron?

I had a similar question a while back: Does the gravitational attraction on a particle increase if it is accelerated to near light speed? Relativity tells us that‚ near light speed, momentum increases to more than just rest mass times velocity. We can interpret this two ways: Either the mass increa...
by lgw
Fri Mar 14, 2014 7:29 pm UTC
Forum: Science
Topic: Planck lengths and length dilation
Replies: 11
Views: 4137

Re: Planck lengths and length dilation

I love Pfhorrest's question. I think "the fabric of the universe" is quantized, but it can't be so in the obvious quantized-spacetime way, for just this reason. I think instead it's quantized in "velocity space" (or perhaps "momentum space" is better), that is: our intu...
by lgw
Fri Mar 14, 2014 12:10 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2958
Views: 711660

Re: RELATIVITY QUESTIONS! (and other common queries)

The reason is actually because of gravity. And inflation. Shortly after the Big Bang, the cosmos shifted away from the gold standard and hyperinflation ensued. The result of such rapid inflation is a universe that is nearly homogeneous. However, in a universe with gravity, homogeneity is actually a...
by lgw
Thu Mar 13, 2014 6:38 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1341: "Types of Editors"
Replies: 88
Views: 25350

Re: Types of Editors

Ptolom wrote:Pffft, Vim makes you immortal.


One place I worked had a car in the parking lot with the plate "VI4LIFE". Perhaps "VI4EVAR" was taken?
by lgw
Tue Mar 11, 2014 5:34 pm UTC
Forum: Coding
Topic: Mild Scripting Rant (argument encapsulation)
Replies: 15
Views: 5970

Re: Mild Scripting Rant (argument encapsulation)

Any scripting rant that doesn't mention that PowerShell is the most evil thing ever in scripting is wrong. So now this thread is whole. :twisted: (Man, how could such a neat idea go so horribly, horribly wrong.) It's worth noting that file systems and shells have different limitations. In the Window...
by lgw
Mon Mar 10, 2014 9:53 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2958
Views: 711660

Re: RELATIVITY QUESTIONS! (and other common queries)

I'm not sure what you're trying to say, but it is still a fact that entropy increases over time in isolated systems. That's exactly why we would have no chickens without the sun. All I'm saying is that our intuitions are misleading. Just like physics works fine in both time directions, anything hum...
by lgw
Fri Mar 07, 2014 1:39 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2958
Views: 711660

Re: RELATIVITY QUESTIONS! (and other common queries)

Well it's an empirical fact that entropy tends to increase, and a statistical one as well. You could say that we assign an arrow of time based on entropy because that's how our brains work, and you would be right, but the second law of thermodynamics is pretty solid. If we defined time in the oppos...
by lgw
Tue Mar 04, 2014 8:31 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2958
Views: 711660

Re: RELATIVITY QUESTIONS! (and other common queries)

Ah, but I don't think the Wikipedia summary is right, is the thing (specifically, the interpretation of the math - I'm sure the math is fine). I don't think its true that as you pass the event horizon, a broad cone in front of you spatially becomes black, because that is the direction you'd (as the...
by lgw
Mon Mar 03, 2014 11:27 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2958
Views: 711660

Re: RELATIVITY QUESTIONS! (and other common queries)

Ah, but I don't think the Wikipedia summary is right, is the thing (specifically, the interpretation of the math - I'm sure the math is fine). I don't think its true that as you pass the event horizon, a broad cone in front of you spatially becomes black, because that is the direction you'd (as the ...
by lgw
Thu Feb 27, 2014 9:55 pm UTC
Forum: Coding
Topic: Coding: Fleeting Thoughts
Replies: 9979
Views: 1979964

Re: Coding: Fleeting Thoughts

Without getting into a quote sniping war, my concern with RAII goes with not using exception handling. If the constructor fails (e.g. out of memory) then what happens if the destructor is called later on? Either the compiler needs to generate code to keep track of which objects were successfully co...
by lgw
Thu Feb 27, 2014 8:28 pm UTC
Forum: Coding
Topic: Resources for learning system design.
Replies: 1
Views: 3132

Re: Resources for learning system design.

A writer writes. A designer designs. There's no other way to learn, AFAIK. So, practice designing simple things. Pick problems, where you understand the problem domain such as your technical specialty or day-to-day stuff, for which there's either an existing automated solution/product, or for which ...
by lgw
Thu Feb 27, 2014 12:40 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2958
Views: 711660

Re: RELATIVITY QUESTIONS! (and other common queries)

Apparently the "quantum firewall" is out now, and we're back to "not notice anything". My favorite physics thought experiment has been a black hole with a 1 light year radius (to the event horizon). You would drift in gently at 1g, with no significant tidal effects, and really s...
by lgw
Thu Feb 27, 2014 12:33 am UTC
Forum: Science
Topic: Centrifugal Delta-V
Replies: 15
Views: 3321

Re: Centrifugal Delta-V

You don't even need to wind in the cable to gain something. You can do something similar to a passive gravity assist, but on bodies to small to have sufficient gravity. You just harpoon it, swing around and release. If your departing vector is more along the body's orbital motion than the approachi...
by lgw
Tue Feb 25, 2014 9:00 pm UTC
Forum: Coding
Topic: Database Design
Replies: 5
Views: 3363

Re: Database Design

Looks like everything_name should be normalized. Reservation #s would be nice. Honestly, this looks more like homework than a real problem, to me. I'd expect 10x the messy details.
by lgw
Tue Feb 25, 2014 12:16 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1334: "Second"
Replies: 47
Views: 14306

Re: 1334: "Second"

For some reason, having my search results tailored to my search history as Google does really annoys me. Fortunately, there is DuckDuckGo. (When I was young, the game was "duck duck goose" - it that some regional thing?). And it may be cliché but it's true: whatever I'm searching for, ther...
by lgw
Mon Feb 24, 2014 8:30 pm UTC
Forum: Fictional Science
Topic: Spaceship intercept question
Replies: 19
Views: 5703

Re: Spaceship intercept question

And if the pursuer has the ability to disable the other ship when they're close together, heading straight towards the attackers no longer sounds like a very smart plan. The thought had occurred... on the other hand, barring EMP, even a minor angular difference would presumably make a physical atta...
by lgw
Mon Feb 24, 2014 8:10 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2958
Views: 711660

Re: RELATIVITY QUESTIONS! (and other common queries)

A freely falling observer passing the event horizon of a sufficiently large classical black hole wouldn't notice anything. There's some controversy about real black holes with quantum effects 1 , although tidal forces would make a mess of you long beforehand with a three solar mass black hole. Also...

Go to advanced search