You seem to be knowledgeable about this topic. The reversible
component designs in the article appear to presuppose a clock signal
without much else said about it. I get that someone might be able to
prototype an individual gate, but is the implementation of a practical
clock distribution network at molecular scales reasonable to take for granted?
To your question: I suppose all you need is for the halide moieties (Br) in your gates to also couple to the halide ions (Br clock?). The experiment you link was conducted at 7K for the benefit of being able to observe it with STM?
That's a different kind of clock, and its clock mechanism is a gradual and somewhat random decrease in the concentration of one reagent until it crosses a threshold which changes the equilibrium constant of iodine. It isn't really related to the kind of clock you use for digital logic design, which is a periodic oscillation whose purpose is generally to make your design insensitive to glitches. Usually you care about glitches because they could cause incorrect state transitions, but in this case the primary concern is that they would cause irreversible power dissipation.
The experiment was conducted at 7K so the molecule would stick to the metal instead of shaking around randomly like a punk in a mosh pit and then flying off into space.
Yeah you're probably right about the clocks but I hope that wouldn't stop people from trying :)
>The experiment was conducted at 7K so the molecule
Br is good at sticking to Ag so I suspect the 7K is mainly (besides issues connected to their AFM^W STM setup) because the Euro dudes love ORNL's cryo engineering :)
Br's orbitals are filled here because it's covalently bonded to a carbon, so it's basically krypton. Experiments with moving atoms around on surfaces with STMs are always done at cryogenic temperatures because that's the only way to do them.
>. Hence, the Br atoms kept the molecules on track, likely because their
interaction with the surface substantially contributed to the barrier for molecular rotation
Yeah that's a reason people prefer AFM (but then they won't be able to do manipulation)?
[Br- is a "good leaving group", not so much at 7K maybe. You are also right in that, above all, they don't want their molecule sticking (irreversibly) to the (tungsten) tip ]
I'm only acquainted with the basics of the topic, not really knowledgeable. It's an interesting question. I don't think the scale poses any problem—the smaller the scale is, the easier it is to distribute the clock—but there might be some interesting problems related to distributing the clock losslessly.
I supervised a few students doing senior research projects back when I
used to be a faculty member. I think a senior project is a different
situation than a master's or Ph.D. thesis because it's more about
demonstrating your employability than making original contributions to
knowledge, and your time is very limited. To that end, it's important
that you finish up with something to show for yourself. Unless you
plan to go into academia, working code counts for more with employers
than a research paper in itself. A null result even when properly
investigated and analyzed is less impressive than a success, so a good
way to hedge your bets is to find two or three competing technologies
addressing the same need, implement a small similar project using each
of them, and compare their relative strengths and weaknesses. That way
you improve your chances of a successful outcome even if not all of
them work out, while also demonstrating a broader variety of skills to
potential employers than you would if you focused on just one thing.
Read enough of the literature to avoid embarrassing yourself but not
to become a world class expert because the latter would waste your
whole year. Be careful of faculty members drawing you down a rabbit
hole. They like thinking about cutting edge research problems, some of
which might be of industrial interest, but even so, no company is
going to put somebody fresh out of school in charge of that regardless
of how smart that person seems to be.
I grabbed an ASUS E210 about a year ago and it's doing great with
Linux on it. It's fanless, with an 11.6" display, 4G of ram, a 1.1 Ghz
celeron, and 64G of storage. You can get one dirt cheap as an ex
display model. I don't know if it's still up, but there was a
surprisingly good repair manual for it on the ASUS web site, showing
in detail how to install an m.2 storage device, so I souped it up with
an additional 8TB of storage, which I'm using for jellyfin, immich,
calibre, and paperless-ngx. It will just about manage to run a
virtualbox vm if you need to do any windows stuff.
> For those who aren't using a @gmail.com, what are you using?
I use gandi.net. It gives me all the aliases I want for free. Other
services I've investigated are better in some ways but are stingy
about aliases. I understand about differential pricing and how it
might make business sense to charge a premium for perqs that cost
nothing to provide, but even if I were to self-identify as a rich
person, the top tier on proton mail, for example, has a limit of
something like ninety aliases. Barely a week goes by that I don't need
a new alias for some business or institution expecting a permanent
irrevocable claim on my attention, and when I printed a bunch of
business cards, I put a different alias on every card in case a
prospect's contact list were to get leaked to spammers.
> coming up with a domain name is hard!
I use [1] for pronounceable made-up names. It hasn't been updated in a
while but is still working fine for me. With patience you can get
words that sound like undiscovered chemical compounds, aristocratic
dynasties, exotic circuit fabrication technologies, science fiction
planet names, ancient goddesses, dystopian megacorps, etc..
I'm of the opinion that animal agriculture by non-sustainable methods
is a major contributor to climate change (maybe even the main
contributor, if you believe these guys [1]), but switching any
significant segment of the population to plant based diets is
politically a non-starter. It isn't talked about and isn't going to
happen. A well funded Manhattan project to make lab grown meat
palatable and economically viable would be the best shot in the
short term at bringing us back from the brink.
What's stopping me is a lack of capital, a lack of relevant expertise,
and a lack of the kind of personality that's useful for convincing
anyone of anything.
Something to keep in mind when selecting a printer with refillable
liquid ink tanks is that they all have an internal waste ink
repository, which is a sponge that soaks up unused ink that apparently
accrues slowly through normal use, or quicker any time you do an ink
purge [1]. On very high end photo printers it's replaceable, and might
be described as a maintenance cartridge in the specs. If it fills up
and can't be replaced, the printer is dead. When I was shopping
around, the only brand I could find that had replaceable waste ink
repositories even at the low end was Canon, and being too cheap even
to have a network interface also saved me the trouble of firewalling
it.
It's true that ink tank printers need to be used regularly or else the
print heads dry out like a felt tip pen. Since the ink costs next to
nothing per page, I print a full page family photo once a week and
hang it up somewhere around the house if I haven't used the printer
for anything else, which still works out cheaper than any
alternatives. The walls look like instagram, but being reminded of
loved ones might not be such a bad thing.
EcoTank printers are particularly hostile with this. Despite that the waste ink pass on most models are user-servicable behind 1-2 screws, and can be purchased on Amazon for $10, the printer displays a message that you must ship the printer to Epson for a full replacement.
In order to bypass the warning, you’ve traditionally needed to use a program like WIC[0], which costs $10 per use(!) - I recommend epson_print_conf[1], which is a little more tailored to the HN crowd, but does not extract a bribe every time you use it.
Not only that, but if the tip is a single point then will the pencil
ever be vertical? That would imply that the pencil's center of mass is
perfectly aligned with the tip relative to the gravitational field
despite both being located in a continuum. Can any mechanism or
natural process bring about an intended zero probability event?
There are similar discussions to be had about arbiters, whose usual
conclusion is that metastability is inevitably resolved by thermal
noise. The article addresses that issue by postulating a vacuum and a
very low absolute temperature, but how would the pencil be shielded
from the gravitational effects of distant bodies in motion? Does this
experiment have to take place in an empty universe?
I think it would be profitable to write a smartphone app that takes the floor plan of a trade show or exhibition hall with the exhibitors' booths shown, allows the user to select the booths he or she wants to visit, and solves the travelling salesman problem. I wonder if it could be licensed to trade show organizers for big bucks by offering kickbacks on all the extras. The extras could include bribes from exhibitors for the heuristic to favor paths that go by them, or that get users to visit them ahead of their competitors, or that push promotions to users redeemable at the booth but only within the next five minutes, or that lets exhibitors buy a list of the names of everyone who selected their booth, or lets them buy a list of the other booths those people also selected, etc..
Here's a crazy idea. Create a large empty file on your VPS. Call it
backingfile.lol. Then remotely mount the directory containing
backingfile.lol using sshfs on your local machine, so that you can
access backingfile.lol as if it were a local file. Then create a
loopback device on the local machine using backingfile.lol as the
backing file, and create a luks device on top of the loopback device.
Format the luks device with the filesystem of your choice, mount the
filesystem, and rsync your secret files with it. Tear down everything
except backingfile.lol on the VPS when not in use, and your files will
persist inside it.
If my understand about all this is correct, your adversary could have
physical access, root access, and Intel's own ME signing keys, but
will see only encrypted data at rest on the VPS, because your keys
never leave the local machine, affording him no recourse short of
cracking AES.
Your comment reminded me of the documentary "Three Identical
Strangers" [1], about identical triplets adopted by different families
during their first months of life who try to re-establish their
connection when they meet later by chance. It's a gripping story with
a shock ending. Somewhat relevant to this thread and I hope not too
much of a spoiler, it's suggested in the film that they may have been
affected by separation anxiety.
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