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Luís F. Simões

Singularity University, class of 2010: projects that aim to impact a billion people wit... - 8 views

www.kurzweilai.net/ty-webinar-today-sneak-preview

AI robotics biomedicine biotechnology electronics energy nanotechnology singularity futures social ethics space synthetic biology computer science defence

shared by Luís F. Simões on 22 Sep 10 - No Cached
  • Luís F. Simões on 22 Sep 10
     
    At the link below you find additional information about the projects: Education: Ten weeks to save the world http://www.nature.com/news/2010/100915/full/467266a.html
  • ...8 more comments...
  • LeopoldS on 23 Sep 10
     
    this is the podcast I was listening to ...
  • Dario Izzo on 23 Sep 10
     
    We can do it in nine :)
  • LeopoldS on 24 Sep 10
     
    why wait then?
  • Juxi Leitner on 24 Sep 10
     
    hmm, wonder how easy it is to get funding for that, 25k is a bit steep for 10weeks :)
  • Dario Izzo on 26 Sep 10
     
    well, we wait for the same fundings they get and then we will do it in nine.... as we say in Rome "a mettece un cartello so bboni tutti". (italian check for Juxi)
  • LeopoldS on 26 Sep 10
     
    and what you think about the project subjects?
  • LeopoldS on 26 Sep 10
     
    I like the fact that there are quite a lot of space projects .... and these are not even bad in my view: The space project teams have developed imaginative new solutions for space and spinoffs for Earth. The AISynBio project team is working with leading NASA scientists to design bioengineered organisms that can use available resources to mitigate harsh living environments (such as lack of air, water, food, energy, atmosphere, and gravity) - on an asteroid, for example, and also on Earth . The SpaceBio Labs team plans to develop methods for doing low-cost biological research in space, such as 3D tissue engineering and protein crystallization. The Made in Space team plans to bring 3D printing to space to make space exploration cheaper, more reliable, and fail-safe ("send the bits, not the atoms"). For example, they hope to replace some of the $1 billion worth of spare parts and tools that are on the International Space Station.
  • Dario Izzo on 26 Sep 10
     
    and all in only a three months summer graduate program!! that is impressive. God I feel so stupid!!!
  • LeopoldS on 26 Sep 10
     
    well, most good ideas probably take only a second to be formulated, it's the details that take years :-)
  • Dario Izzo on 26 Sep 10
     
    I do not think the point of the SU is to formulate new ideas (infact there is nothing new in the projects chosen). Their mission is to build and maintain a network of contacts among who they believe will be the 'future leaders' of space ... very similar to our beloved ISU.
Thijs Versloot

Dwarf planet could illuminate the dark sector - 1 views

physicsworld.com/...uld-illuminate-the-dark-sector

science gravity dark energy matter einstein

shared by Thijs Versloot on 17 Jul 14 - No Cached
  • Thijs Versloot on 17 Jul 14
     
    A dwarf-planet candidate called UX25 and its tiny satellite could provide the first evidence of a new cosmological model that includes antigravity, say Alberto Vecchiato and Mario Gai of the Astrophysical Observatory of Turin in Italy.
Thijs Versloot

Black Hole Analogue Discovered in South Atlantic Ocean - 0 views

www.technologyreview.com/...overed-in-south-atlantic-ocean

science physics

shared by Thijs Versloot on 23 Aug 13 - No Cached
  • Thijs Versloot on 23 Aug 13
     
    Vortices in the South Atlantic are mathematically equivalent to black holes, say physicists, an idea that could lead to new ways of understanding how currents transport oil and garbage across oceans Black holes are regions of spacetime in which gravity is strong enough to prevent anything escaping, even light.
Dario Izzo

Optimal Control Probem in the CR3BP solved!!! - 7 views

math.u-bourgogne.fr/...research

OCP CR3BP trajectory MAD

shared by Dario Izzo on 07 Jun 11 - No Cached
  • Dario Izzo on 07 Jun 11
     
    This guy solved a problem many people are trying to solve!!! The optimal control problem for the three body problem (restricted, circular) can be solved using continuation of the secondary gravity parameter and some clever adaptation of the boundary conditions!! His presentation was an eye opener ... making the work of many pretty useless now :)
  • ...13 more comments...
  • Ma Ru on 08 Jun 11
     
    Riemann hypothesis should be next... Which paper on the linked website is this exactly?
  • Joris _ on 08 Jun 11
     
    hmmm, last year at the AIAA conference in Toronto I presented a continuation approach to design a DRO (three-body problem). Nothing new here unfortunately. I know the work of Caillau, although interesting what is presented was solved 10 years ago by others. The interest of his work is not in the applications (CR3BP), but in the research of particular regularity conditions that unfortunately make the problem limited practically. Look also at the work of Mingotti, Russel, Topputo and other for the (C)RTBP. Smart-One inspired a bunch of researchers :)
  • Dario Izzo on 08 Jun 11
     
    Topputo and some of the others 'inspired' researchers you mention are actually here at the conference and they are all quite depressed :) Caillau really solves the problem: as a one single phase transfer, no tricks, no misconvergence, in general and using none of the usual cheats. What was produced so far by other were only local solutions valid for the particular case considered. In any case I will give him your paper, so that he knows he is working on already solved stuff :)
  • Dario Izzo on 08 Jun 11
     
    Answer to Marek: the paper you may look at is: Discrete and differential homotopy in circular restricted three-body control
  • Joris _ on 08 Jun 11
     
    Ah! with one single phase and a first order method then it is amazing (but it is still just the very particular CRTBP case). The trick is however the homotopy map he selected! Why this one? Any conjugate point? Did I misunderstood the title ? I solved in one phase with second order methods for the less restrictive problem RTBP or simply 3-body... but as a strict answer to your title the problem has been solved before. Nota: In "Russell, R. P., "Primer Vector Theory Applied to Global Low-Thrust Trade Studies," JGCD, Vol. 30, No. 2", he does solve the RTBP with a first order method in one phase.
  • Joris _ on 08 Jun 11
     
    I think what is interesting is not what he solved, but how he solved the problem. But, are means more important than end ... I dunno
  • Dario Izzo on 08 Jun 11
     
    I also loved his method, and it looked to me that is far more general than the CRTBP. As for the title of this post, OK maybe it is an exageration as it suggests that no solution was ever given before, on the other end, as Marek would say "come on guys!!!!!"
  • Joris _ on 09 Jun 11
     
    The generality has to be checked. Don't you think his choice of mapping is too specific? he doesn't really demonstrate it works better than other. In addition, the minimum time choice make the problem very regular (i guess you've experienced that solving min time is much easier than mass max, optimality-wise). There is still a long way before maximum mass+RTBP, Topputo et al should be re-assured :p Did you give him my paper, he may find it interesting since I mention the homotopy on mu but for max mass:)
  • Dario Izzo on 09 Jun 11
     
    Joris, that is the point I was excited abut, at the conference HE DID present solutions to the maximum mass problem!! One phase, from LEO to an orbit around the moon .. amazing :) You will find his presentation on line.... (according to the organizers) I gave him the reference to you paper anyway, but no pdf though as you did not upload it on our web pages and I could not find it in the web. So I gave him some bibliography I had with be from the russians, and from Russell, Petropoulos and Howell, As far as I know these are the only ones that can hope to compete with this guy!!
  • Joris _ on 09 Jun 11
     
    for info only, my phd, in one phase: http://pdf.aiaa.org/preview/CDReadyMAST08_1856/PV2008_7363.pdf I prefered Mars than the dead rock Moon though!
  • Dario Izzo on 09 Jun 11
     
    If you send me the pdf I can give it to the guy .. the link you gave contains only the first page ... (I have no access till monday to the AIAA thingy)
  • LeopoldS on 11 Jun 11
     
    this is why I like this Diigo thingy so much more than delicious ...
  • tvinko on 17 Jun 11
     
    What do you mean by this comment, Leopold? ;-) Jokes apart: I am following the Diigo thingy with Google Reader (rss). Obviously, I am getting the new postings. But if someone later on adds a comment to a post, then I can miss it, because the rss doesn't get updated. Not that it's a big problem, but do you guys have a better solution for this? How are you following these comments? (I know that if you have commented an entry, then you get the later updates in email.) (For example, in google reader I can see only the first 5 comments in this entry.)
  • LeopoldS on 18 Jun 11
     
    I like when there are discussions evolving around entries
  • LeopoldS on 18 Jun 11
     
    and on your problem with the RSS Tamas: its the same for me, you get the comments only for entries that you have posted or that you have commented on ...
jcunha

Why are the Dutch so tall - 1 views

phys.org/...04-tall-story-dutch-tower.html

FUN

shared by jcunha on 08 Apr 15 - No Cached
  • jcunha on 08 Apr 15
     
    Following a discussion with Kzrystof, where he came up with gravity anomaly reasons for why Dutch people are so tall. Funny to see this fact gathers scientific attention as well.
  • Dario Izzo on 15 Apr 15
     
    We solved this darwinian riddle years ago. They must be tall in order to find their partners above the fog and thus reproduce in the dutch weather.
Nicholas Lan

gravity doesn't exist - 2 views

vixra.org/0907.0018

fun nutter

shared by Nicholas Lan on 09 Jun 10 - No Cached
  • Nicholas Lan on 09 Jun 10
     
    apparently warm things attract each other instead. a symbolic prize of a virtual launch vehicle based on a smeg fridge/freezer for the most amusing/shortest refutation. "A ~1068 gm hollow copper sphere hovers above a 1000 W heat element." "After power was applied to the heat element for 400 s, the means of the first and last ~6 force measures indicate that the sphere's gravitational mass increased by 1.9 % or 20 gm."
  • ...1 more comment...
  • Luzi Bergamin on 09 Jun 10
     
    I didn't know the viXra project. It's a great help to the PHYS RF at ACT. Whoever posted something there is crackpot for sure...
  • pacome delva on 09 Jun 10
     
    interesting...
  • LeopoldS on 09 Jun 10
     
    this looks like absolute humbug to me .... reminds me of some rotating superconductors :-)
Joris _

SPACE.com -- Space Beer Headed for Zero Gravity Bar - 0 views

www.space.com/...testing-space-beer-100927.html

shared by Joris _ on 28 Sep 10 - No Cached
  • It may not come in time for Oktoberfest, but the world's first beer to be certified for consumption in space will soon undergo tests in weightlessness to see if it is brewed with the right stuff.
Joris _

Japan plans to send a robot to the moon | The Australian - 1 views

www.theaustralian.com.au/...story-e6frg8y6-1225947783972

robot space moon

shared by Joris _ on 04 Nov 10 - No Cached
  • the little android's oil bearings and ultrasonic sensors will not work in the lunar vacuum
  • The one-sixth gravity presents problems for stable movement, and Moon dust clogs joints.
  • the Japan Aerospace Exploration Agency (Jaxa), the country's space agency. It runs the rockets needed to deliver their robot to the Moon and, so far, has been distinctly cool on the idea.
  • Joris _ on 04 Nov 10
     
    Interesting! I like the quote "Maybe China would allow that to be a one-way trip but, in Japan, it would have to be a return ticket" talking about a human mission ....
santecarloni

[1011.6263] Electrostatic accelerometer with bias rejection for Gravitation and Solar S... - 6 views

arxiv.org/1011.6263

PHY gravity

shared by santecarloni on 30 Nov 10 - No Cached
  • santecarloni on 30 Nov 10
     
    Is it really true?
  • pacome delva on 02 Dec 10
     
    Article 1011.6263 doesn't exist
  • pacome delva on 03 Dec 10
     
    ha it's back! Yes they are talking about GAP since some time in France, and lobbying to put it on a planetary mission.
LeopoldS

Phys. Rev. Lett. 105, 211303 (2010): Model for Gravity at Large Distances - 2 views

prl.aps.org/...e211303

phy science astronomy pioneer anomaly

shared by LeopoldS on 18 Nov 10 - No Cached
  • LeopoldS on 18 Nov 10
     
    Sante have a look at this ... Daniel is the TU researcher who did the study I was sending you a few years ago with Luzi - very nice and smart guy .... Luzi: now you will have difficulties in shooting :-)
pacome delva

New pulsars could net gravitational waves - 0 views

physicsworld.com/...41364

phy pulsars gravitational_waves

shared by pacome delva on 11 Jan 10 - Cached
  • One of the physicists working on interferometers, Jim Hough of the University of Glasgow, agrees that pulsar timing is a good way to search for gravity waves at extremely low frequencies. He believes that if astronomers observe 20 pulsars with a timing precision of better than 100 nanoseconds for five years then they would "have a very good possibility of observing gravitational-wave signals."
  • pacome delva on 11 Jan 10
     
    Again an article about the gravitational waves detected with pulsars. However its a bit fast conclusion, cause i don't know any serious article that draw this conclusion for sure...
Joris _

NASA will miss Congressional deadline for asteroid tracking - Science Fair - USATODAY.com - 0 views

blogs.usatoday.com/...ine-for-asteroid-tracking.html

MAD NEO

shared by Joris _ on 25 Jan 10 - Cached
  • he panel finds the 2005 order to find 90% of Earth-threatening asteroids 460 feet or larger infeasible,
  • No method for diverting asteroids has been experimentally demonstrated
  • Options include a "gravity tractor" orbiting slow-moving objects and tugging them off course with tidal tugs, a "kinetic" impact of a heavy spacecraft into an asteroid, or a nuclear explosion
  • ...1 more annotation...
  • Unlike the dinosaurs, we are smart enough to do the math and figure out the answer that modest resources should be dedicated to the problem
    • Joris _
      Joris _ on 25 Jan 10
       
      "we are smart enough" is a completely subjective comment. Reading the article it does not give the same impression :|
pacome delva

Galaxy study backs general relativity - 1 views

physicsworld.com/...41948

galaxy general_relativity gravitational_lensing survey

shared by pacome delva on 16 Mar 10 - Cached
  • The observed ratio, dubbed EG, has a value of 0.39 ± 0.06. This agrees with general relativity, which predicts a value of 0.4. Crucially, the measurement rules out the tensor, vector scalar (TeVeS) model of modified gravity, which has an EG of 0.22 and does not need dark matter. The result does not, however, preclude the f(R) theory – which is more similar to general relativity and has EG values in the 0.328–0.365 range.
  • pacome delva on 16 Mar 10
     
    mmm, i wonder if this study takes into account the non linearities studied in the Ariadna on galaxies...
  • LeopoldS on 16 Mar 10
     
    Luzi: any comment?
Joris _

Gravity-defying ramps take illusion prize : Nature News - 6 views

www.nature.com/...news.2010.233.html

mathematics

shared by Joris _ on 17 May 10 - No Cached
pacome delva liked it
  • pacome delva on 18 May 10
     
    excellent !
Giusi Schiavone

Antigravity Machine Patent Draws Physicists' Ire - 2 views

news.nationalgeographic.com/...1111_051111_junk_patent.html

anti-gravity

shared by Giusi Schiavone on 19 Jan 11 - Cached
  • Giusi Schiavone on 19 Jan 11
     
    Antigravity Machine Patent
  • Luzi Bergamin on 19 Jan 11
     
    Do they aim for the Ig Nobel prize?? Just great!!
pacome delva

Galaxy clusters back general relativity - 0 views

physicsworld.com/...47358

phy general_relativity galaxy mond teves f(r)_gravity

shared by pacome delva on 30 Sep 11 - No Cached
  • The Copenhagen group discovered that the redshifts agreed with the predictions of both general relativity and f(R) gravity, the theory that tries to avoid dark energy. However, the error bars on the redshifts excluded MOND and TeVeS, the theories that try to avoid dark matter.
nikolas smyrlakis

Should NIAC be Revived? | NASA Watch - 0 views

www.nasawatch.com/...should_niac_be.html

niac advanced concepts nasa space

shared by nikolas smyrlakis on 12 Jun 09 - Cached
  • $4 million annual budge
    • nikolas smyrlakis
      nikolas smyrlakis on 12 Jun 09
       
      To my knowledge (readers correct me if I'm wrong) no where else within NASA do people get paid to just think very long range ideas. My question: does such a group belong in NASA and should it or something like it be revived? And if you think so, what should its highest priority be? Propulsion? Artificial gravity systems? Space Elevator?
  • nikolas smyrlakis on 12 Jun 09
     
    about the advanced concepts institute of NASA. Found via twitter
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