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Riding horses, hacking computers, phones and smartwatch.
pavel

Pavel Machek

Reply to @tymoty@f.cz
@tymoty Spousta lidi by chtela text ktery strucne a jasne vysvetli moderni fyziku. Ja take :-).
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pavel

Pavel Machek

Reply to @xChaos@f.cz
@xChaos @askihk @tymoty @sibrosan S temihle prirovnanimi bych byl velmi opatrny. Nekde jinde jste takhle udelal uvahu ze hranice pozorovatelneho vesmiru by mela mit teplotu nula kelvinu; to rozhodne neni samozrejme (a myslim ze to tak neni).
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pavel

Pavel Machek

Reply to @xChaos@f.cz
@xChaos @askihk @tymoty @sibrosan Tak sci-fi si rad prectu, ale...

Ranny vesmir a vzdaleny vesmir je prece to same, ne? To je myslim celkem uznavane.

A podle me je uznavane i to ze se Zeme proti CMB pohybuje, a robot souhlasi.

A jasne, soucasna kosmologie ma nejake problemy, ale "vidime moc galaxii v rannem vesmiru" myslim neni jedna z nich, uvitam odkaz.

--

Pohybuje se zeme proti CMB?

ChatGPT said:
Ano, Země (resp. Sluneční soustava) se vůči reliktnímu záření (CMB) pohybuje. To se projevuje dipólovou anisotropií CMB – jedno směřování vesmíru se jeví o něco teplejší a opačné směřování o něco chladnější kvůli Dopplerovu jevu.

Konkrétně:

Rychlost Sluneční soustavy vůči CMB je asi 370 km/s.

Směr pohybu je zhruba směrem k souhvězdí Raka (Leo).

Tento pohyb nezávisí na rotaci Země kolem Slunce nebo na rotaci Země kolem své osy, ty mají mnohem menší efekt (~30 km/s pro oběh kolem Slunce).

Takže ano, Země/Sluneční soustava není v klidu vůči CMB – CMB nám vlastně poskytuje „absolutní“ kosmologické referenční rámce“.
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pavel

Pavel Machek

Reply to @xChaos@f.cz
@xChaos @askihk @tymoty @sibrosan Tak ja si troufnu :-). https://en.wikipedia.org/wiki/Quasar
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pavel

Pavel Machek

Reply to @xChaos@f.cz
@xChaos @askihk @tymoty @sibrosan ??? ??? ?..? Ja myslel ze "pozorovatelny vesmir" je velmi dobre definovany pojem? https://en.wikipedia.org/wiki/Observable_universe . A vidite tady nejake galaxie? https://en.wikipedia.org/wiki/Cosmic_microwave_background Ja ne, ale vas post chapu tak, ze by tam mely byt -- CMB je rude posunuty ranny vesmir. Soucasna kosmologie ma nejake problemy, ale jine nez zminujete...
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pavel

Pavel Machek

Reply to @askihk@defcon.social
@askihk @tymoty @xChaos @sibrosan Kdyz tohle neni o prachu jako spis o horizontu udalosti :-).
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pavel

Pavel Machek

Reply to @askihk@defcon.social
@askihk @sibrosan @xChaos @tymoty Tady asi doporucim neco jako "PBS spacetime" na yt? O vesmiru toho vime dost, ale "utvar" bych asi nepouzil, a bylo by potreba rozlisovat pozorovatelny vesmir.. No a pak tam bude nejaka filozofie jestli casti vesmiru ktere nemuzem pozorovat jeste tedy jsou nas vesmir a tak. Proste je to celkem slozite :-).
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pavel

Pavel Machek

I'm playing with angular velocity sensor on #librem5. I can get some data from sysfs, and they show hw is working, but interface is not fast enough for anything useful. I did not get triggering / buffered mode to work so far. Code is at git@github.com:pavelmachek/Espruino.git .
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pavel

Pavel Machek

Reply to @z3ntu@fosstodon.org
@z3ntu Ok, so apparently it is possible to buy Fairphone 5 and 6 new here, for similar prices (cca EUR600). Second-hand Fairphone 5 may be available for ~EUR400, and new Fairphone 4 may be available for ~EUR300.

Having main camera available with open-source drivers sounds very cool and may be reason for Fairphone 4 ... unless same is true for the newer models...?
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pavel

Pavel Machek

Reply to @tymoty@f.cz
@tymoty Is Earth the centre of the Universe? Is there centre of Universe? You may want to select better example, as, well, Earth is almost as good centre of Universe as any other. (Ok, there's cosmic microwave background and Earth moves against it, but what does not?)
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pavel

Pavel Machek

Reply to @dcz@fosstodon.org
@dcz You are partly right.

OTOH JITs are optimized for speed, while cargo build is optimized, well, for best optimized result. If you can get 2% faster output executable for 30% slower compilation, compiler might do it.
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pavel

Pavel Machek

Reply to @z3ntu@fosstodon.org
@z3ntu Aha, that's it, thanks. If you want video recording & autofocus, take a look here: https://gitlab.com/tui/tui/-/tree/master/ccam?ref_type=heads . It can also take photos, some work will be required.

I wonder how easy is it to get Fairphone 4 in czech republic?
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pavel

Pavel Machek

Reply to @z3ntu@fosstodon.org
@z3ntu Aha, so my recall was that problem with OnePlus6 was not sensors, but phy inside the SoC, and that it was common problem accross Qualcomm chips. Look like I was wrong.
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pavel

Pavel Machek

Reply to @dcz@fosstodon.org
@dcz Well. You are building x86 code on one side and arm code on other. More fair benchmark would be to cross-build same demo for, dunno, powerpc.
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pavel

Pavel Machek

Reply to @z3ntu@fosstodon.org
@z3ntu If I understand things correctly, that's a very good news for OnePlus 6, too? And maybe a TODO item for me, as Droidian is likely not going to work for these experiments.
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pavel

Pavel Machek

Reply to @z3ntu@fosstodon.org
@z3ntu @jbaersaft Slower charging also means battery lifetime is longer. Limiting charge to 80% is even more important. I have some experiments at https://github.com/pavelmachek/unicsy_demo/tree/master/bat and elsewhere.
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pavel

Pavel Machek

Reply to @QuadRadical@wetdry.world
@QuadRadical @z3ntu There's also AF support for Millipixels, Megapixels and Clicks machine, to mention a few. Last one can do PDAF. But there's a lot of difference between "AF support" and "good AF support".
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pavel

Pavel Machek

Prasatko od baterky je takova zvlastni vec. Ono neni objekt, takze vlastne neexistuje, a muze porusovat fyzikalni zakony. Treba dokaze fakt neuveritelny zrychleni, a muze se pohybovat nadsvetelne.

Chapu, ze je to zlutakovi podezrele. Velke prasatko mu nevadi (nevadilo?) ale kdyz se zaostri... tak se zlutak pokusi take pohybovat nadsvetelne. Nastesti neuspesne.
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pavel

Pavel Machek

Reply to @Petr90@mastodonczech.cz
@Petr90 Preju Rajchlovi spravedlnost, jakou si zaslouzi, a nam ostatnim, aby to bylo co nejdriv...
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pavel

Pavel Machek

Reply to @jan@social.dytrych.cloud
@jan @xChaos Tak reasoning je neco jineho, ne? A AI hype je lepsi ignorovat. Jsou to LLM, na modelovani jazyka jsou dobre, na odpovidani na otazky min.

(Asi by slo zkusit dat vystup modelu jinemu modelu, at to zkusi overit jestli to dava nebo nedava smysl, ale...)
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