HN user
This is fun! but not so surprising to me:
987,654,321 + 123,456,789 = 1,111,111,110
1,111,111,110 + 123,456,789 = 1,234,567,899 \approx 1,234,567,890
So 987,654,321 + 2 x 123,456,789 \approx 10 x 123,456,789
Thus 987,654,321 / 123,456,789 \approx 8.
If you squint you can see how it would work similarly in other bases. Add the 123... equivalent once to get the base-independent series of 1's, add a second time to get the base-independent 123...0.
There is Smartsheet, which mostly works well for this, but its power-user features are pretty limited compared to Excel.
Are you sure? I recall that the dish was spherical, not parabolic, and had a movable receiver mounted on cables; moving the receiver adjusts the direction from which signals can be received. Indeed, Wikipedia claims that it was steerable [0].
Sorry, that should say “coherence length”.
No defects needed for flux penetration in a type-II superconductor. When the conference length is smaller than the penetration depth (up to a factor of sqrt(2)), flux vortices can nucleate as soon as the surface magnetic field gets above the lower critical field Bc1.
Yes, black holes are theorized to evaporate due to Hawking radiation [0].
There is a nice calculator for terminal velocity of a sphere in air here:
http://hyperphysics.phy-astr.gsu.edu/hbase/airfri2.html
That being said, I'm not sure how relevant terminal velocity is for anything but the smallest/slowest ends of the parameters of this app. For an asteroid going 38,000 mph (default speed on linked page), drag just doesn't play a big part - the asteroid passes through the atmosphere in ~5 seconds, not enough time for it to slow down significantly.
This sounds like a kind of historical GeoGuessr.
I think OP means “disconnected past” as the spacelike-separated region south of the “now” slice. Boosting could transform points in this region into the spacelike-like separated region in the “future” (i.e. the “disconnected future), no? The points are not transforming across the light cone boundary, just across the arbitrary “now” plane.
Regarding the turn signals - do you use a right-hand-drive car? Is the turn signal stalk on the right side? OP's description is consistent with my left-hand-drive experience, with the stalk on the left.
You are off by a factor of ten [0].
[0] https://home.cern/resources/faqs/facts-and-figures-about-lhc
I think this is the difference between two kinds of "wanting", the id kind and the superego kind. We want the chips because they taste good. We want the nutritious food because we understand on a conceptual level that it is healthy. What we choose to eat in the end depends on how we balance these desires in the moment.
Insert analogies for the news as appropriate.
I suspect much of the Morse that you hear is radio amateurs (hams) talking to each other. Morse, being a very narrow bandwidth signal, is hardy against noise and low power situations - depending on the band, it is often not hard to talk with someone thousands of miles away using only a few watts.
Are there really any microwave ovens that use klystrons? I thought most if not all commercial microwave ovens used magnetrons.
For those interested in growing tropical & sub-tropical plants from seed - mangoes, avocados, citrus, papayas, etc. - Melvin Wei [0] has a great youtube channel. There is a certain hacker spirit to his approach, with lots of experimentation in getting these somewhat atypical houseplants to grow in pots.
I have had a good experience with the browser plugin floccus, which I use to sync bookmarks to a self-hosted NextCloud instance. It has cross browser support. I have a 'sync' folder that is shared across all browsers/devices, as well as local-only bookmarks on each device (home/work/mobile/etc.)
1 meter is about 27 orders of magnitude down from 100 Gly, and 12 up from 1 pm (approximately the proton radius). So we are closer to the small side.
For some time now, for buying home improvement tools, I have followed the heuristic “buy the cheap one, then once it breaks, buy the expensive high-quality one.” I find that this helps make sure I don’t waste money on something I will only use once or twice.
I think the "track count" has to do with the number of tracks available for mixing in the sound editing stage, not how many channels are in the final mix. At the time the sound editors would have been limited by the mixing board itself - how many tapes can run simultaneously. These days, computer audio workstations can have essentially an unlimited number of tracks, allowing endless tinkering and post-production that can become a crutch. My experience is in music production but I think the same applies to film.
I would expand on this to say that they propose to use an innovative cavity shape. Normal-conducting cavities can reach higher accelerating fields than superconducting cavities, but at much lower duty factors and with high voltage breakdown events. This new design would allow for lower power dissipation than typical normal-conducting structures, ultimately allowing higher RF duty factors.
There are still some downsides/tradeoffs compared to superconducting structures, including a much smaller beam aperture (5 mm diameter vs. ~100 mm for superconducting cavities), which disrupts the quality of the beam. Superconducting machines can also be run in continuous wave mode (100% duty factor), and state-of-the-art niobium cavities have been driven at ~50 MV/m in CW.
If property values in my neighborhood go up will I be forced to sell or refinance my house to pay the tax bill?
Pardon my ignorance, but isn’t that how it works (outside of California)? My understanding is that in almost all US tax districts, property values are assessed periodically and the tax liability of the owner changes year on year with the value of the property.
As an accelerator physicist - while some earlier machines were built without vacuum beamlines, nearly all modern[0] accelerators are built with ultra-high vacuum beamlines. Beam quality greatly degrades in contact with residual gas due to scattering. This is especially important in light sources, but really any machine where you want low emittance.
[0] edit - I should specify that I mean high energy machines here (my focus). There are also many low energy machines that don't require high vacuum at the end - medical accelerators for example.
I'm in a very similar boat. My best solution so far has been to use Onenote and Outlook plus paper, but I'm looking for something better. Maybe org-mode or a personal wiki?
In Outlook I mark emails that I want to respond to/deal with later as "unread" or else apply the "followup" flag depending on how much work responding will take. There are downsides but I have so far been able to keep the scheme manageable (single-digit quantities with the unread/followup tags at any given time).
I use a paper notebook, physical sticky notes, and scraps of paper for general notes depending on how ephemeral their importance is.
I use Onenote for meeting notes and a running to-do list, as well as a rough knowledge base, but it's far from perfect:
- You can organize notes but you are sort of locked into the organization scheme that you start with. If you discover some orthogonal knowledge organization/symmetry across topics, there's not a good way to reorganize. For instance, say a certain topic gets discussed in different contexts in different weekly meetings. If you already have note sections with deep histories for Meeting 1 and for Meeting 2, how do you link instances of Topic A across meetings in some useful way?
- For to-do lists, it's easy to start with one list of all your tasks, but as these get complicated with subtasks, you might organize them into different sections, and eventually different pages... but now the to-do list is actually spread across fifteen different note sections, and are you really going to read each one at the start of each day?
They're not totally separate concepts though, no? The definite integral is the difference of two values of the indefinite integral (antiderivative).
I suppose if you're talking about solving them computationally, you can calculate/approximate the definite integral by taking the limit of the sum as you reduce the step size, whereas performing the indefinite integral requires a different method (chain rule etc.). But when doing them by hand usually the first step in calculating a definite integral is finding the antiderivative.
“It will soon be second nature”
That’s for sure!
Homebrewing - the most expensive way to enjoy free beer.
Nope, any orbit. Think of it this way: an orbiting particle (or piece of debris) with no independent control/thrust will stay along whatever orbital path it's following, round and round (modulo any further orbital decay). After a collision, the particle is on a new elliptical trajectory, but the new trajectory still passes through the location of the collision. So the lowest point of the new orbit cannot be any higher than the altitude of the collision.
Likewise, if the particle is slowed down, the highest point of the new orbit cannot be any lower than than the altitude of the collision.
An interesting feature of orbital mechanics is that a change in velocity at a given point in orbit will change the altitude of the orbit at every point except where the change took place.
If "time slows down over time" then we would still observe the light at its original frequency - why would the energies of the states of hydrogen atoms in distant stars change over time, but the energies of the photons emitted long ago not change?
How does this hypothesis account for the CMB?
Wikipedia has a nice summary of alternative cosmological theories (and why they are often dismissed by experts):
https://en.wikipedia.org/wiki/Non-standard_cosmology#Proposa...
if two points are separated by an interval equal to C
If d = c, I don't think it determines the values of x, y, z, and t. What if x = 2c, y = z = 0, and t = 1? Unless I'm not following your logic correctly. In my recollection, for two given points in spacetime, d is invariant but the values of x, y, z, and t depend on the observer's frame of reference.
You can't really compare the energy of a particle beam to temperature - temperature is only really defined in equilibrium and macroscopically.
Also, from the article,
"In the new method, conditions sufficient for fusion are created in the confines of the metal lattice that is held at ambient temperature."