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freeztar

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  1. Like
    freeztar got a reaction from techdubai in Wireless HP and linux   
    Have you tried this?
     
    [ubuntu] Unable to install hplip for HP Printer - Ubuntu Forums
  2. Like
    freeztar got a reaction from techdubai in Wireless HP and linux   
    :)
     
    I agree. Using Ubuntu explicitly means you are *not* a computer moron. :D
     
    Btw, how is the scanning on that printer in Ubuntu? When I searched for a solution for you, I came across lots of threads about people having terrible scan quality with this printer.
  3. Like
    freeztar got a reaction from petrushkagoogol in Mountain Shape   
    I was thinking about this the other day. In this age of alternative facts, it forces people to speak in absolutes.
     
    My thoughts on this matter started after I read a lively debate on Pluto being a planet, or not. Mountains are the same. It just depends on perception at this point, but we could easily set standards. As Turtle described, there are a lot of factors to consider. So rather than an easy answer, you would have to consult a taxonomic field guide to know for sure that what you are looking at is a defacto mountain (and not just a silly looking hill).
     
    I propose a few standards:
     
    1. Height - What is it's height relative to sea level? What is it's heigh relative to the surrounding area?
    2. Mountain chains - Mountains do not usually appear out of nowhere solitarily. They are usually connected to a seismic event. In those cases, there is usually a long chain of mountains. Mountains in these areas should be considered mountains by association.
    3. Sudden elevation - hills are generally thought of as low, rolling bumps in the landscape. You'd walk to the top of one in your finest suit without breaking a sweat. Mountains, on the other hand, require the right footwear and a good heart. The climb is steeper. The elevation changes more rapidly with a mountain. This can easily be quantified. All the good hiking guides will tell you the change of elevation over distance. Some of them even come with graphs. So if we call x distance and y elevation, we can come up with an equation that satisfies the mountain test. But then we get into methodology and it gets really messy here. Which side of the "mountain" are you measuring? Where does the measuring tape begin and end? Messy...
     
    So really, it doesn't matter that much. You say potato and I say pootawto.
  4. Like
    freeztar reacted to jwferk in Is A Photon Torpedo Possible?   
    New thought experiment (although this one can be done in a lab)
     
    Photons exert radiation pressure.  In fact, the effects of radiation pressure need to be accounted for in some ultrasensitive measuring devices.  They also make "solar sail" propulsion possible.
     
    Consider building a two boxes.  One of these has a reflective surface on the inner side with 99.9% reflective efficiency.  The other has an inner reflective surface of 100% efficiency.  In the latter instance we truly have a "black box" since any light entering the box is continuously reflected on the inside of the box.
     
    Put a standard light bulb next to each and turn it on.
     
    Question - 
     
    1 - will the first box (99.9% efficiency) get brighter with time as more photons enter from the light bulb?
    2 - will one or both boxes eventually explode from radiation pressure as the number of photons entering exceeds those exiting (photons build up inside)?
    3 - do the boxes heat up with time?
    4 - what happens if we continuously shine a laser beam into either box?
    5 - will it take box one (99.9% efficiency) longer to dim (photon escape) if the light bulb is left on for 2 hr instead of 1 hr?  Presumably there are more photons trapped inside.
     
    Cheers,
    jwferk aka kref
  5. Like
    freeztar reacted to CraigD in Is A Photon Torpedo Possible?   
    You’d need something more complicated than simply a reflective surface inside the boxes, because a simple reflector would reflect incoming light as well as outgoing. There are optical devices, called optical isolators, that allow more light to pass thought them in one direction than the other, so you could in principle make a box like you describe, jwferk.
     
    The problem with the scheme is that the best reflectors have less than 100% reflectance. The best, which multiple layers of dielectric materials, have reflectance on the order of 99.999% over a broad range of angles.
     
    A bit of arithmetic can show that this would give a “half life” for the light stored inside a 1 m diameter box (for simplicity, spherical) of about 0.0002312 seconds. This is pretty amazing, but it means that after 1 second, the box would have only about 1/24325 (1/101302) its original amount of light. There are only about 1089 photons in the universe (source), so even if the box started with all of them, it would be empty in less than 0.07 s.
     
    It is possible, via total internal reflection, to have 100% reflectance, but only when the “reflector” has a lower refractive index than what the light’s traveling through, and the light strikes the reflector at an angle less (more acute) than a critical value.
     
    So, though a box with light striking a reflector at many angles, some near 90deg can’t store light, maybe you could do it with something like a loop of optical fiber.
  6. Like
    freeztar reacted to superpsycho in The Underlying Problem Of Understanding "reality"   
    You have a lot here Doctordick, so let's start with the issues you ran into in college. Professors and instructors, like most people, develop a comfort zone, which they are reluctant to leave, especially when dealing with new concepts they have difficulty understanding. A lot of people today come out of higher education locked into what has been drummed into them. It seems you've been able to avoid that situation.

    As for genius, it's a word I dislike more than a little. Genius is nothing more than having a knack for doing something. Usually, it relates to some form of pattern recognition or ability to remember things. It certainly doesn't mean someone is all knowing about everything.

    As for the substance of your thesis, The Foundations of Physical Reality. Reality is based on a range of perception and what is repeatable. If something can only be detected once in ten thousand years, it's rather difficult to develop a proof that it exists.

    You've recognized a number of flaws, often outright contradictions, in man's understanding of physical existence. You recognize something is missing and look to quantify what that is by analyzing what is actually observed compared to what theory says should be observed then extrapolating what might be missing.

    Any formula can only account for the known factors. It cannot account for the unknown, especially when what is unaccounted for consists of a range of variables that could change based on context. One of the major factors man has yet to understand is the nature of the void, or space, itself. And, as you've correctly pointed out, what we perceive, or our interpretation of that perception, may not be correct. That makes any attempt to understand existence difficult, if not outright impossible, by observation alone.

    To understand the true nature of the universe, I would suggest you start from scratch. Trying to do it piecemeal usually isn't that productive and you're just building on what is likely a flawed foundation. Even question the way man sees existence itself. Try looking at E=MC² from another angle. Consider there is only one constant in the formula, C². That would mean 'E' and 'M' are just states of velocity.

    Perhaps our perception of the universe as an X, Y and Z coordinate system is inverted. Perhaps the universe is motion and X, Y and Z are established by the relative states of that motion. Perhaps Gravity is not a thing but an object's reaction to the differential affect upon it by curved space.

    Try to build a logical universe that doesn't have the flaws the current models do, then test it against observation.
  7. Like
    freeztar reacted to Rade in The Underlying Problem Of Understanding "reality"   
    Why do you look for feedback here ?   You make a claim that Einstein equation of general relativity is not complete, that it is missing your radial term.  OK, let us suppose you are correct.   There must be 100s of professional physicists in the world that would consider themselves to have advanced knowledge of general relativity, and I suspect none of them read this forum. 
     
    So, write up your ideas presented here and submit them to a peer reviewed journal that deals with general relativity theory.  You may need to submit to more than one journal to find a journal editor that will submit your presentation for peer review.   After you receive the peer review letters, post them here so we can see what they have to say, and you can let us know why they use their knowledge of Einstein to hide their stupidity.  
  8. Like
    freeztar reacted to GAHD in The Cosmological Constant, Lamda Cdm, And The Expansion Of The Universe   
    Math? Here you go.

    Dark energy? Here you go. http://www.scienceforums.com/topic/28443-a-universe-from-nothing-krauss/?view=findpost&p=336707

    My crazy-gut-feeling on gravitons is that they don't exist. That Tesla was right to think of an ethertic substrate upon which our universe is stretched, and that this substrate accounts for both gravitational and electomagnetic feilds and feild lines. Related random "can't prove it but it makes things fit" being that photons are actually paired particles rotatating around each other on(and through) the brane between "normal" space and this etheric substrate. Makes polarisation, the duality of the photonic feild, scatter, etc make more sense to me from a geometric perspective. 
    There was another thread around here recently...this one..Where I discussed my take on some recent LIGO results in relation to the second 'here you go" above. Craig, bless his puritan understanding. cut it off with a 1980's standard model as defacto, and I'm rather too busy to dredge up and spoon feed advances from the past 5 years to show the "more complete" alternative models floating around the post-doc community now vs the 80's textbooks. Take a read, look though the various links (some are a bit dry and  others are colorful laymans). I hope it helps you in your mission from zeus.
  9. Like
    freeztar got a reaction from JMJones0424 in What I Learned As A Hired Consultant For Autodidact Physicists   
    Great article from a theoretical physicist that started a consulting job for amateur physicists.
     
    https://aeon.co/ideas/what-i-learned-as-a-hired-consultant-for-autodidact-physicists
  10. Like
    freeztar reacted to CraigD in Laser Sailing   
    This article seems to me to be a lot of updated discussion of an idea proposed by the late Robert Forward is papers and books such as his 1995 book Indistinguishable from Magic. In 1985, Forward proposed sending many tiny robotic probes to interesting nearby extrasolar stars by accelerating them with Earth-orbiting solar powered microwave lasers, with would be financed by the lasers then being turned to the Earth’s surface to provide commercial power. He called this idea Starwisp. I believe he actually patented in the hope it would be done within his lifetime and make him rich and famous, mindful of speculation that Arthur Clarke should have patented his 1945 idea for geosynchronous satellites. 
    Being 30 years old, there’s a lot of commentary on how it could or could not be done, much by Geoffrey Landis – the Wikipedia article has a reasonably good synopsis of it.
     
    Key features of the Starwisp idea include
    The probes are only pushed about as far as the orbit of Mars, at which point it’s no longer possible to aim the microwave beam precisely enough. They’re accelerate strongly, though, at 2+ gs, so could reach speeds greater than 0.01 the speed of light, c. The probes don’t have their own power supplies. When they reach their destination, a less powerful microwave beam is sent to them to power their sensors and communication systems, allowing them to collect data and radio it back to earth. A lot – hundreds or thousands – of them could be mass-produced and flown, so the choice of target destinations is simple: all of them. Forward was especially interested in discovering and exploring nearby brown dwarf sub-stellar objects. Forward wasn’t, I recall, as optimistic, expecting Starwisp missions to take many decades, but not many centuries. 
    The equations (non-relativistic, OK for estimates of speeds only a small fraction of c) for time and speed for a constant acceleration and distance are
    [math]t= \sqrt{\frac{2d}{a}}[/math]
    [math]v= \sqrt{2da}[/math]
    So here are some examples:

    a d v t (m/s/s) (AU) (c) (days) 10 0.5 0.0041 1.42 24 2.5 0.0142 2.05 100 2.5 0.0289 1.00 2500 6 0.2238 0.31 100 50 0.1292 4.48 360 50 0.2451 2.36 150 120 0.2451 5.67 So to get the needed speed, you’d need to do something likeaccelerate the probe at 36 gs to the aphelion of Pluto,
    at 15 gs to the heliopause,
    or at 250 gs to the orbit of Jupiter.
     
    None out outside of the realm of the reasonably possible, but none look easy, either.
  11. Like
    freeztar got a reaction from Turtle in Wildflowers   
    If we had years, Mr. Turtle, I'd be wasting them on some remote solar system island. Make it so!
     
     
    Burke uses the key you are about to get. :)
     
    Take note that this is an old guide. These poor guys did this for their doctoral thesis.
    Nomenclature has changed a bunch and you will have to keep that in mind. Scientiic names are still *way* better, but when you get into a mess with species, you may find that things have changed. :(
     
    Fortunately, this should be easy to resolve with today's awesome internet resources.
     
     
    I'm assuming you've also got a invasive list in hand. That is almost always the best list to check first. ;)
     
    White lomatium? Did I miss one that you posted? I've just seen yellow.
     
     
    I love your new-ish posting style. :confused:
     
    I'll have a better look at it in a bit. It's hard to keep up with the Turtle-pace lately. ;)
  12. Like
    freeztar reacted to JMJones0424 in Pearl Powder Vs. Caco3   
    To be honest, I'm not sure that you can. I've tried for years to convince my sister that her practice of ear candling is not just useless, but could possibly be detrimental. I've come to realize that at times people don't act rationally. And if you don't actively try to be rational, beliefs can easily override evidence. You'll have to evaluate the situation yourself, but sometimes it appears to me to be best to just let others have their irrationalities if the harm isn't significant. If someone I knew claimed that ground oyster shell cured cancer, I would vehemently resist the claim. If someone claimed ground pearls reduced wrinkles, I'd lay out the scientific evidence against the claim and then leave it be, as the continued confrontation isn't worth it beyond that.
  13. Like
    freeztar reacted to Bolitoglossa in Do We Know Of Any Possible Alternatives For Base Pairs In Either Dna Or Rna?   
    Hello Maddog,
     
    Let me make a small correction to your second post; bases are not amino acids, they are nucleotides. Amino acids are the building blocks of proteins, and chemically dissimilar to nucleotides. Three bases will code for a specific amino acid to be incorporated into a growing protein chain.
     
    The answer to your question is yes - scientists have been able to find alternative base pairs. A very good example is the 7-(2-thienyl)-imidazo[4,5-b]pyridine (Ds) and pyrrole-2-carbaldehyde (Pa) pair, published in Nature Methods in 2006. (Hirao, Ichiro, et al. "An unnatural hydrophobic base pair system: site-specific incorporation of nucleotide analogs into DNA and RNA." Nature Methods 3.9 (2006): 729-735.)
     

     
     
    This specific pair will not form hydrogen bonds with each other like the regular bases, but will rather pair through hydrophobic packing.
     
     
    You can find other examples in the literature.
     
    I am currently working (as an undergrad) in a lab with "unnatural" or "non-canonical" amino acids. We evolve the genetic machinery in ways that allow us to modify the genetic code so that we can genetically incorporate new amino acids not found in nature, giving new useful properties to proteins. It is not necessary to use new base pairs to do this, as we can simply "hijack" some of the codons (there are 64 codons, 61 code for 20 amino acids, 3 codons are "stop" codons, we usually hijack one of the three stop codons, the UAG). However, new base pairs will become very useful once the technology expands.
  14. Like
    freeztar got a reaction from Turtle in Quatrain Corner   
    I came
    I saw
    I left
    I'm back!
  15. Like
    freeztar got a reaction from DFINITLYDISTRUBD in Vesica Piscis--real Sacred Geometry   
    My wife and I had fun making this. It took about 3 hours and it was worth every second. :bdayhappy_balloons:

  16. Like
    freeztar reacted to maddog in Quality Of Light On Other Planets   
    The answer to your question is in two parts:
    1) The first part is easy. This is just color (frequencies) of light from the sun. Our sun being a G2 IV main sequence star with the central wavelength around 580 nm or so (yellow).
    2) The hard part is what would the color you would see somewhere (another planet). This depends on many things: the absorption properties of the atmosphere of the planet you are on (assuming there is one). This depends on the atmospheric density which is likely dependent on elevation and how thick the atmosphere is. If the atmosphere is thick enough to support vapor suspension then yes, clouds may form which can attenuate light depending upon frequency. Humidity is also relevant as is the current local temperature and pressure. Know what the atmosphere is composed of will help to determine what wavelengths of light might be absorbed.
     
    I know this didn't really answer it other than give you some ideas upon which to enhance your search. Good Luck! :D
     
    maddog
  17. Like
    freeztar got a reaction from DFINITLYDISTRUBD in Perpetual motion does exsist   
    No, it doesn't. If you think that it does, then prove it.
     
     
    ok...but why does it have to be God?
     
    Again, prove that energy can be created or destroyed.
     
     
    The universe as a whole is undefinable by default. There is no way to make such claim.
  18. Like
    freeztar reacted to Turtle in Underwater Volcanism   
    news from home...stop we have an unprecedented new view of some undersea volcanoes...stop. see full article & video @ link...go (there is nothing like deep water for a disaster. ;))

    Undersea mountains march into the abyss @ bbc
  19. Like
    freeztar got a reaction from Michaelangelica in Water: Where will it come from in 2050?   
    Aye, true enough.
    Biomagnification of the toxins is much worse than a diluted-polluted water source. (ie, eating fish from Lake Eerie is much worse than drinking the surface water, by an EXTREME magnitude)
  20. Like
    freeztar got a reaction from Michaelangelica in Water: Where will it come from in 2050?   
    You do realize that Lake Eerie is probably the biggest settling pond in the world, right?
     
    You could dredge up some lake-bottom soil and apply it to your skin for some DDT-fortified protection from the killer mosquitoes up there though. :hihi:
  21. Like
    freeztar reacted to Mister Agenda in Chipped Brains   
    So we could have a car that comes when we whistle? I think that would be cool. Mine does know how to play dead, though.
  22. Like
    freeztar reacted to DFINITLYDISTRUBD in Testing A Smiley   
    :computerkeys::xx::doh::crash: :cussing::censored::crash::computerkick::cussing::censored::computerkick::coffee_n_pc:
    Wow I'm still here!
  23. Like
    freeztar reacted to pamela in Fungi & Lichens   
    this is looking mighty tasty :P
  24. Like
    freeztar reacted to pamela in Fungi & Lichens   
    i loves me some lichen :)
  25. Like
    freeztar reacted to Turtle in Fungi & Lichens   
    a place for fungi & lichen photos, links, stories, discoveries, and otherwise related posts.
     
    this is a relatively new area for me. i went hiking today to look for flowers but found fungi & lichens instead. here we goes then.
     
    lichen definition @ freedictionary.com
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