Magnetic bits and transistor elements are shrinking rapidly. They could reach the atomic scale within the next few decades. But matter on a small scale can have very odd properties. How will engineers and designers exploit a world dominated by quantum effects?
Anyone who is not shocked by quantum theory has not understood it! Shocking indeed to find that quantum bits, or qubits, can be both 1 and 0 at the same time! Or that it can be impossible to eavesdrop on a message sent as qubits! Scientists are exploiting such quantum weirdness to build quantum logic gates as a step towards a super-powerful quantum computer. In other work they are inventing ultra-secure crytography systems in which data is coded in the quantum states of individual photons.
On February 25, the Electronic Frontier Foundation (EFF) and four law school clinics announced the launch of a website and project that has been established to educate Internet users about their rights online. The Chilling Effects Clearinghouse provides detailed information about the legal rights of Internet users regarding "cease-and-desist" letters (letters sent from entities claiming violation of copyright or trademark and other grievances and threatening legal action if the violating party does not cease and desist). The project currently provides basic legal information on issues like copyright and the Digital Millennium Copyright Act, trademark and domain names, anonymous speech, and defamation.
The Chilling Effects website includes a forum for Internet users to post their cease-and-desist letters to an online clearinghouse. Students at the participating law clinics will review the letters and annotate them with links to explain applicable legal rules. The four Internet law clinics currently involved are Harvard, Stanford, the University of California at Berkeley, and the University of San Francisco, and the project is expected to grow to include additional law schools.
Posted letters will remain online in a searchable database that interested parties can consult to find information that relates to their particular situation. "The Internet makes it easier for individuals to speak to a wide audience, but it also makes it easier for other people and corporations to silence that speech," said Wendy Seltzer, Fellow at Harvard's Berkman Center for Internet and Society, who created the project and website. "Chilling Effects aims to level the field by helping online speakers to understand their rights in the face of legal threats."
These sort of measures are expected to happen, and I find it not so surprising. Cybersquatting has become less and less a term in our collective vocabulary, and I find it hard to belevive that the majority would feel apprehensive about a law, for all intents and purposes, is already in place. Common sence would have told me to not choose a name used by corporations in other countires.
Be that as it may, there are certain individuals who may be innocent in the matter, and find themselves in a whole heap of trouble down the road if they failed to do the research needed for a new domain name.
Astrometry - Planetary measurements
on
42 Worlds in 32 Days
·
· Score: 2, Informative
This is a repost of an error that was pointed out to me in an earlier reply I made. This isn't an attempt at spam, just an attempt to help clear up a mistake on my part, but moreso, to make better known, what I feel is good and informatave reading.
My original reply was more of enthusiasm then accuracy however, I do stand corrected. You are correct when it comes to using Doppler efects to measure bodies in motion, particularly 2 bodies in orbit around each other. I realised later that I had used the wrong term to decribe what was in my minds eye. The term I should have used, was Astrometry.
Astrometry, is used to determine the proper motion of a star, using other stars as reference points. If a body is revolving around a star then the body will affect the circular motion of the star. As one measures the stars linear motion, it will be found that the motion is not in a straight line, but rather in a wobbly line due to the presence of a planet or planets revolving around the star. This situation is similar to observing a person spinning a shotput around his or her body. The person shows a wobbling type motion due to the heavy load that is being rotated about his or her body. The person represents the star while the shotput represents a planet. In addition, the person can move from point A to point B while the shotput is revolving. Therefore, there are two motions, the wobbly motion caused by the rotation of the shotput, and the linear motion caused by the movement of the person. If the person was not rotating a shotput and simply walking, then the only motion observed would be the distance from point A to point B, and no wobble in the motion would occur. This, of course, presupposes that the person is sober. In like manner, if one were to observe the proper motion of a star without any planets revolving about it, then the distance the star moves from point A to point B would not reflect a wobbling motion, the motion would be in a straight line.
Radial velocity, which is measured by the doppler effect (lines in the stars spectrum) takes into account the line-of-sight velocity; i.e. the velocity of which a star is moving towards or away from us. If the light from the star is moving towards us then the spectrum of the star will be shifted to the blue portion of the spectrum (blueshift) and the velocity would be negative. If, on the other hand, the star is moving away from us then the spectrum of the star will be shifted to the red portion of the spectrum (redshift) and the velocity will be positive. By observing the spectral shift one can determine the rate at which the star is moving.
How does this relate to the detection of planetary bodies revolving around stars? If a planet or planets revolve around a star then the motion of the star will be affected. According to Alan Boss, writing in Physics Today, if a star is orbiting around the center mass of a system, then it suggests a planetary body or bodies revolving about it. More to the point, if the above is true then there would be a periodic shift in the doppler velocity. This is the star's spectrum would exhibit a shift to the red and then to the blue, and then to the red, periodically. In other words, the effect of planetary bodies around a star will affect the radial velocity of the star so that it would be moving towards us and then away from us, and continue to repeat that pattern. It should be noted that the perturbation or doppler velocity shift is very small, and therefore, extremely difficult to detect.
Many of the ensuing discoveries rely heavily upon radial velocity techniques. Highly specialized spectrographs, that can detect tiny doppler-induced wavelength shifts in a star's spectra are used to calculate the radial velocities. However, it will be of no surprise to note that the planets that were discovered using this technique are large and/or are in tight orbits, because this technique disposes itself to that type of finding.
The direct imaging method is based on the fact that planets reflect the stars' light. Planets do not give off any light of their own. For example, the various planets we see in the night sky are a result of the sun's light reflecting from them. Likewise, planets around other suns would also reflect the light of their suns. This method is used in order to determine reflected light from an extrasolar planet. It is obvious that only extremely large planets may be detected using this method. The major problem with this technique is that the star is much brighter than the planet it illuminates, and can tend to obfuscate it.
Photometry can be used to detect a change in the brightness of a star, as in the case when a planet occults a star. On Earth we can observe this during a solar eclipse. That is, our Earth occults our Sun during an eclipse. As an extrasolar planet revolves about its star, it will pass between its star and the line of sight as seen from the Earth. A change in the brightness of the star due to this transit would then suggest a planetary body.
Earth sized bodies would indeed be almost invisible to Dopler shift searches, but developments are are already well underway to correct this problem. I have submitted a post on this subject,mostly consisting of links, but I am still waiting for it to be authorized. If it should be declined, I will write something up on it in a reply to this post for the sake of discussion.
My original reply was more of enthusiasm then accuracy however, I do stand corrected. You are correct when it comes to using Doppler efects to measure bodies in motion, particularly 2 bodies in orbit around each other. I realised later that I had used the wrong term to decribe what was in my minds eye. The term I should have used, was Astrometry.
Astrometry, is used to determine the proper motion of a star, using other stars as reference points. If a body is revolving around a star then the body will affect the circular motion of the star. As one measures the stars linear motion, it will be found that the motion is not in a straight line, but rather in a wobbly line due to the presence of a planet or planets revolving around the star. This situation is similar to observing a person spinning a shotput around his or her body. The person shows a wobbling type motion due to the heavy load that is being rotated about his or her body. The person represents the star while the shotput represents a planet. In addition, the person can move from point A to point B while the shotput is revolving. Therefore, there are two motions, the wobbly motion caused by the rotation of the shotput, and the linear motion caused by the movement of the person. If the person was not rotating a shotput and simply walking, then the only motion observed would be the distance from point A to point B, and no wobble in the motion would occur. This, of course, presupposes that the person is sober. In like manner, if one were to observe the proper motion of a star without any planets revolving about it, then the distance the star moves from point A to point B would not reflect a wobbling motion, the motion would be in a straight line.
Radial velocity, which is measured by the doppler effect (lines in the stars spectrum) takes into account the line-of-sight velocity; i.e. the velocity of which a star is moving towards or away from us. If the light from the star is moving towards us then the spectrum of the star will be shifted to the blue portion of the spectrum (blueshift) and the velocity would be negative. If, on the other hand, the star is moving away from us then the spectrum of the star will be shifted to the red portion of the spectrum (redshift) and the velocity will be positive. By observing the spectral shift one can determine the rate at which the star is moving.
How does this relate to the detection of planetary bodies revolving around stars? If a planet or planets revolve around a star then the motion of the star will be affected. According to Alan Boss, writing in Physics Today, if a star is orbiting around the center mass of a system, then it suggests a planetary body or bodies revolving about it. More to the point, if the above is true then there would be a periodic shift in the doppler velocity. This is the star's spectrum would exhibit a shift to the red and then to the blue, and then to the red, periodically. In other words, the effect of planetary bodies around a star will affect the radial velocity of the star so that it would be moving towards us and then away from us, and continue to repeat that pattern. It should be noted that the perturbation or doppler velocity shift is very small, and therefore, extremely difficult to detect.
Many of the ensuing discoveries rely heavily upon radial velocity techniques. Highly specialized spectrographs, that can detect tiny doppler-induced wavelength shifts in a star's spectra are used to calculate the radial velocities. However, it will be of no surprise to note that the planets that were discovered using this technique are large and/or are in tight orbits, because this technique disposes itself to that type of finding.
The direct imaging method is based on the fact that planets reflect the stars' light. Planets do not give off any light of their own. For example, the various planets we see in the night sky are a result of the sun's light reflecting from them. Likewise, planets around other suns would also reflect the light of their suns. This method is used in order to determine reflected light from an extrasolar planet. It is obvious that only extremely large planets may be detected using this method. The major problem with this technique is that the star is much brighter than the planet it illuminates, and can tend to obfuscate it.
Photometry can be used to detect a change in the brightness of a star, as in the case when a planet occults a star. On Earth we can observe this during a solar eclipse. That is, our Earth occults our Sun during an eclipse. As an extrasolar planet revolves about its star, it will pass between its star and the line of sight as seen from the Earth. A change in the brightness of the star due to this transit would then suggest a planetary body.
Earth sized bodies would indeed be almost invisible to Dopler shift searches, but developments are are already well underway to correct this problem.
I have submitted a post on this subject,mostly consisting of links, but I am still waiting for it to be authorized. If it should be declined, I will write something up on it in a reply to this post for the sake of discussion.
And to think we have just begun to scratch the surface of these extra-solar planetary bodies in their discovery. So far to date, all we have been able to easily spot is gas giants, much like Jupiter. With clearer, more deeper peering telescopes, we will soon be able to see more spherical aberition for smaller, earth size objects.
At the current rate of discovery, and current rate of advancing techniques to discover these objects, it truly is a good time to live in this age of discovery!
Slashdot Mirror
Anyone who is not shocked by quantum theory has not understood it! Shocking indeed to find that quantum bits, or qubits, can be both 1 and 0 at the same time! Or that it can be impossible to eavesdrop on a message sent as qubits! Scientists are exploiting such quantum weirdness to build quantum logic gates as a step towards a super-powerful quantum computer. In other work they are inventing ultra-secure crytography systems in which data is coded in the quantum states of individual photons.
My appologies, it was there last time I checked.
On February 25, the Electronic Frontier Foundation (EFF) and four law school clinics announced the launch of a website and project that has been established to educate Internet users about their rights online. The Chilling Effects Clearinghouse provides detailed information about the legal rights of Internet users regarding "cease-and-desist" letters (letters sent from entities claiming violation of copyright or trademark and other grievances and threatening legal action if the violating party does not cease and desist). The project currently provides basic legal information on issues like copyright and the Digital Millennium Copyright Act, trademark and domain names, anonymous speech, and defamation.
The Chilling Effects website includes a forum for Internet users to post their cease-and-desist letters to an online clearinghouse. Students at the participating law clinics will review the letters and annotate them with links to explain applicable legal rules. The four Internet law clinics currently involved are Harvard, Stanford, the University of California at Berkeley, and the University of San Francisco, and the project is expected to grow to include additional law schools.
Posted letters will remain online in a searchable database that interested parties can consult to find information that relates to their particular situation. "The Internet makes it easier for individuals to speak to a wide audience, but it also makes it easier for other people and corporations to silence that speech," said Wendy Seltzer, Fellow at Harvard's Berkman Center for Internet and Society, who created the project and website. "Chilling Effects aims to level the field by helping online speakers to understand their rights in the face of legal threats."
Be that as it may, there are certain individuals who may be innocent in the matter, and find themselves in a whole heap of trouble down the road if they failed to do the research needed for a new domain name.
My original reply was more of enthusiasm then accuracy however, I do stand corrected. You are correct when it comes to using Doppler efects to measure bodies in motion, particularly 2 bodies in orbit around each other. I realised later that I had used the wrong term to decribe what was in my minds eye. The term I should have used, was Astrometry.
Astrometry, is used to determine the proper motion of a star, using other stars as reference points. If a body is revolving around a star then the body will affect the circular motion of the star. As one measures the stars linear motion, it will be found that the motion is not in a straight line, but rather in a wobbly line due to the presence of a planet or planets revolving around the star. This situation is similar to observing a person spinning a shotput around his or her body. The person shows a wobbling type motion due to the heavy load that is being rotated about his or her body. The person represents the star while the shotput represents a planet. In addition, the person can move from point A to point B while the shotput is revolving. Therefore, there are two motions, the wobbly motion caused by the rotation of the shotput, and the linear motion caused by the movement of the person. If the person was not rotating a shotput and simply walking, then the only motion observed would be the distance from point A to point B, and no wobble in the motion would occur. This, of course, presupposes that the person is sober. In like manner, if one were to observe the proper motion of a star without any planets revolving about it, then the distance the star moves from point A to point B would not reflect a wobbling motion, the motion would be in a straight line.
Radial velocity, which is measured by the doppler effect (lines in the stars spectrum) takes into account the line-of-sight velocity; i.e. the velocity of which a star is moving towards or away from us. If the light from the star is moving towards us then the spectrum of the star will be shifted to the blue portion of the spectrum (blueshift) and the velocity would be negative. If, on the other hand, the star is moving away from us then the spectrum of the star will be shifted to the red portion of the spectrum (redshift) and the velocity will be positive. By observing the spectral shift one can determine the rate at which the star is moving.
How does this relate to the detection of planetary bodies revolving around stars? If a planet or planets revolve around a star then the motion of the star will be affected. According to Alan Boss, writing in Physics Today, if a star is orbiting around the center mass of a system, then it suggests a planetary body or bodies revolving about it. More to the point, if the above is true then there would be a periodic shift in the doppler velocity. This is the star's spectrum would exhibit a shift to the red and then to the blue, and then to the red, periodically. In other words, the effect of planetary bodies around a star will affect the radial velocity of the star so that it would be moving towards us and then away from us, and continue to repeat that pattern. It should be noted that the perturbation or doppler velocity shift is very small, and therefore, extremely difficult to detect.
Many of the ensuing discoveries rely heavily upon radial velocity techniques. Highly specialized spectrographs, that can detect tiny doppler-induced wavelength shifts in a star's spectra are used to calculate the radial velocities. However, it will be of no surprise to note that the planets that were discovered using this technique are large and/or are in tight orbits, because this technique disposes itself to that type of finding.
The direct imaging method is based on the fact that planets reflect the stars' light. Planets do not give off any light of their own. For example, the various planets we see in the night sky are a result of the sun's light reflecting from them. Likewise, planets around other suns would also reflect the light of their suns. This method is used in order to determine reflected light from an extrasolar planet. It is obvious that only extremely large planets may be detected using this method. The major problem with this technique is that the star is much brighter than the planet it illuminates, and can tend to obfuscate it.
Photometry can be used to detect a change in the brightness of a star, as in the case when a planet occults a star. On Earth we can observe this during a solar eclipse. That is, our Earth occults our Sun during an eclipse. As an extrasolar planet revolves about its star, it will pass between its star and the line of sight as seen from the Earth. A change in the brightness of the star due to this transit would then suggest a planetary body.
Earth sized bodies would indeed be almost invisible to Dopler shift searches, but developments are are already well underway to correct this problem. I have submitted a post on this subject,mostly consisting of links, but I am still waiting for it to be authorized. If it should be declined, I will write something up on it in a reply to this post for the sake of discussion.
Astrometry, is used to determine the proper motion of a star, using other stars as reference points. If a body is revolving around a star then the body will affect the circular motion of the star. As one measures the stars linear motion, it will be found that the motion is not in a straight line, but rather in a wobbly line due to the presence of a planet or planets revolving around the star. This situation is similar to observing a person spinning a shotput around his or her body. The person shows a wobbling type motion due to the heavy load that is being rotated about his or her body. The person represents the star while the shotput represents a planet. In addition, the person can move from point A to point B while the shotput is revolving. Therefore, there are two motions, the wobbly motion caused by the rotation of the shotput, and the linear motion caused by the movement of the person. If the person was not rotating a shotput and simply walking, then the only motion observed would be the distance from point A to point B, and no wobble in the motion would occur. This, of course, presupposes that the person is sober. In like manner, if one were to observe the proper motion of a star without any planets revolving about it, then the distance the star moves from point A to point B would not reflect a wobbling motion, the motion would be in a straight line.
Radial velocity, which is measured by the doppler effect (lines in the stars spectrum) takes into account the line-of-sight velocity; i.e. the velocity of which a star is moving towards or away from us. If the light from the star is moving towards us then the spectrum of the star will be shifted to the blue portion of the spectrum (blueshift) and the velocity would be negative. If, on the other hand, the star is moving away from us then the spectrum of the star will be shifted to the red portion of the spectrum (redshift) and the velocity will be positive. By observing the spectral shift one can determine the rate at which the star is moving.
How does this relate to the detection of planetary bodies revolving around stars? If a planet or planets revolve around a star then the motion of the star will be affected. According to Alan Boss, writing in Physics Today, if a star is orbiting around the center mass of a system, then it suggests a planetary body or bodies revolving about it. More to the point, if the above is true then there would be a periodic shift in the doppler velocity. This is the star's spectrum would exhibit a shift to the red and then to the blue, and then to the red, periodically. In other words, the effect of planetary bodies around a star will affect the radial velocity of the star so that it would be moving towards us and then away from us, and continue to repeat that pattern. It should be noted that the perturbation or doppler velocity shift is very small, and therefore, extremely difficult to detect.
Many of the ensuing discoveries rely heavily upon radial velocity techniques. Highly specialized spectrographs, that can detect tiny doppler-induced wavelength shifts in a star's spectra are used to calculate the radial velocities. However, it will be of no surprise to note that the planets that were discovered using this technique are large and/or are in tight orbits, because this technique disposes itself to that type of finding.
The direct imaging method is based on the fact that planets reflect the stars' light. Planets do not give off any light of their own. For example, the various planets we see in the night sky are a result of the sun's light reflecting from them. Likewise, planets around other suns would also reflect the light of their suns. This method is used in order to determine reflected light from an extrasolar planet. It is obvious that only extremely large planets may be detected using this method. The major problem with this technique is that the star is much brighter than the planet it illuminates, and can tend to obfuscate it.
Photometry can be used to detect a change in the brightness of a star, as in the case when a planet occults a star. On Earth we can observe this during a solar eclipse. That is, our Earth occults our Sun during an eclipse. As an extrasolar planet revolves about its star, it will pass between its star and the line of sight as seen from the Earth. A change in the brightness of the star due to this transit would then suggest a planetary body.
Earth sized bodies would indeed be almost invisible to Dopler shift searches, but developments are are already well underway to correct this problem. I have submitted a post on this subject,mostly consisting of links, but I am still waiting for it to be authorized. If it should be declined, I will write something up on it in a reply to this post for the sake of discussion.
At the current rate of discovery, and current rate of advancing techniques to discover these objects, it truly is a good time to live in this age of discovery!