Solar-pumped laser power transmission, a way to dramatically decrease launch costs?
in [Physics]
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From: William Mook on 7 Feb 2010 13:49 On Jan 5, 9:09 pm, David Spain <nos...(a)127.0.0.1> wrote: > David Spain <nos...(a)127.0.0.1> writes: > > As opposed to: > > > V(n+1) = (aV(n) + c) mod m > > > where: > > > m > 0 > > 0 < a < m > > 0 <= c < m > > 0 <= Vo < m (and if c=0, Vo > 0) <-- > > FYI, this is wrong, if c=0, Vo must be co-prime to m. > > Sorry. > > ;-) > > Dave The growth factor leading to exponential growth in my original Jan 2 post was based on organic or natural feedback that is known to occur in nature/society/industry. What is the natural or organic process that leads inevitably to the modulo function you claim here? Unintended consequences? Resource depletion? How does that work? I presume you don't need to know how exponential growth works in an infinite field of resources right? I mean, we have reached limits to growth - assuming we stay on Earth. Assuming we move off-world, we have not reached limits to growth. Given the fact that very high living standards lead to ZPG reproductive rates - exponential growth will stop - if we take the next step. Also, if that happens after interstellar transport develops, human density will drop to nearly zero 200 light years from Earth. If this is a general rule, and if technical civilizations are more than 200 light years apart - this answers the Fermi Paradox. Check it out. Population is stable in a subsistence culture. As the people industrialize, their population growth rates rise -peaking about 2% per year - at about $10,000 per person per year (in 2008 dollars) - then, as per capita income rises above $10,000 per person per year population growth rate declines - until it reaches ZPG at $30,000 per person per year - AND NEGATIVE THEREAFTER. Since economic growth rates under ideal conditions can be maintained at 6% or more per year, we can see that unlimited development off world leads naturally to a situation where population peaks. The peak will be determined by how fast economic growth is maintained. Any economic hiccup or reversal leads to massive spikes in population - until there is a collapse due to depletion or pollution or disease or war. Which is another modulo function I suppose. But I'm more interested in positive visions of the future. If we could sustain 6% growth rate in our economy today, using off- world assets, we would see our population peak at 9.12 billions by 2032. (see table below) The interesting thing Year Income Population $/Year 2008 $70,000 6.80 $10,294.12 2009 $74,200 6.93 $10,700.89 2010 $78,652 7.07 $11,128.18 2011 $83,371.12 7.20 $11,577.39 2012 $88,373.39 7.33 $12,050.04 2013 $93,675.79 7.47 $12,547.81 2014 $99,296.34 7.60 $13,072.53 2015 $105,254.12 7.72 $13,626.23 2016 $111,569.37 7.85 $14,211.11 2017 $118,263.53 7.97 $14,829.63 2018 $125,359.34 8.10 $15,484.51 2019 $132,880.90 8.21 $16,178.73 2020 $140,853.75 8.33 $16,915.66 2021 $149,304.98 8.44 $17,699.02 2022 $158,263.28 8.54 $18,532.99 2023 $167,759.07 8.64 $19,422.25 2024 $177,824.62 8.73 $20,372.10 2025 $188,494.10 8.81 $21,388.50 2026 $199,803.74 8.89 $22,478.24 2027 $211,791.97 8.96 $23,649.05 2028 $224,499.48 9.01 $24,909.79 2029 $237,969.45 9.06 $26,270.65 2030 $252,247.62 9.09 $27,743.43 2031 $267,382.48 9.11 $29,341.82 2032 $283,425.42 9.12 $31,081.88 After this point, population begins to fall off; 2033 $300,430.95 9.11 $32,982.47 2034 $318,456.81 9.08 $35,066.00 2035 $337,564.22 9.04 $37,359.22 2036 $357,818.07 8.97 $39,894.37 2037 $379,287.15 8.88 $42,710.63 2038 $402,044.38 8.77 $45,856.12 2039 $426,167.05 8.63 $49,390.64 It is unlikely that population will decline faster than 2% per year - given the fact that people live for more than 50 years. In fact longevity increases will limit the decline to less than 1% once universally applied 2040 $451,737.07 8.46 $53,389.33 2041 $478,841.29 8.29 $57,747.64 2042 $507,571.77 8.13 $62,461.73 2043 $538,026.08 7.96 $67,560.65 2044 $570,307.64 7.80 $73,075.80 2045 $604,526.10 7.65 $79,041.17 2046 $640,797.66 7.50 $85,493.52 2047 $679,245.52 7.35 $92,472.58 2048 $720,000.26 7.20 $100,021.36 2049 $763,200.27 7.05 $108,186.37 2050 $808,992.29 6.91 $117,017.91 By 2050 there will be as many people alive then as there are today, and the world will be generating nearly a quadrillion dollars per year, and the average family of four will be earning nearly $1 million per year! We can have commodity starships and space colonies driven by sun orbiting solar pumped laser light sail by 2025 - 2050 time frame. Bob Forward, chief scientist at Hughes Aerospace showed in 1983 that such vehicles were capable of 1/3 light speed. So, adjusting our figures for this at 2050 0.2% reduction of underlying population - due to life span exceeding 500 years and 4% per year leaving the Earth to points beyond and increasing income growth to 8% per year to reflect increasing automation and robotics we have the following charts after 2050 Total population continues to decline slowly and income skyrockets 2050 $808,992.29 6.91 $117,017.91 2051 $873,711.67 6.90 $126,632.61 2052 $943,608.60 6.89 $137,037.29 2053 $1,019,097.29 6.87 $148,296.87 2054 $1,100,625.08 6.86 $160,481.58 2055 $1,188,675.08 6.84 $173,667.44 2056 $1,283,769.09 6.83 $187,936.71 2057 $1,386,470.62 6.82 $203,378.40 2058 $1,497,388.26 6.80 $220,088.85 2059 $1,617,179.33 6.79 $238,172.31 2060 $1,746,553.67 6.78 $257,741.57 2061 $1,886,277.97 6.76 $278,918.74 2062 $2,037,180.20 6.75 $301,835.91 2063 $2,200,154.62 6.74 $326,636.05 2064 $2,376,166.99 6.72 $353,473.89 2065 $2,566,260.35 6.71 $382,516.83 2066 $2,771,561.17 6.70 $413,946.07 2067 $2,993,286.07 6.68 $447,957.67 2068 $3,232,748.95 6.67 $484,763.81 2069 $3,491,368.87 6.66 $524,594.10 2070 $3,770,678.38 6.64 $567,697.03 2071 $4,072,332.65 6.63 $614,341.47 2072 $4,398,119.26 6.62 $664,818.43 2073 $4,749,968.80 6.60 $719,442.79 2074 $5,129,966.31 6.59 $778,555.32 2075 $5,540,363.61 6.58 $842,524.79 2076 $5,983,592.70 6.56 $911,750.28 2077 $6,462,280.12 6.55 $986,663.63 2078 $6,979,262.53 6.54 $1,067,732.18 2079 $7,537,603.53 6.52 $1,155,461.68 2080 $8,140,611.81 6.51 $1,250,399.41 2081 $8,791,860.76 6.50 $1,353,137.64 2082 $9,495,209.62 6.48 $1,464,317.29 2083 $10,254,826.39 6.47 $1,584,631.93 2084 $11,075,212.50 6.46 $1,714,832.15 2085 $11,961,229.50 6.45 $1,855,730.19 2086 $12,918,127.86 6.43 $2,008,205.01 2087 $13,951,578.09 6.42 $2,173,207.83 2088 $15,067,704.33 6.41 $2,351,767.99 2089 $16,273,120.68 6.39 $2,544,999.43 2090 $17,574,970.33 6.38 $2,754,107.60 2091 $18,980,967.96 6.37 $2,980,397.00 2092 $20,499,445.40 6.36 $3,225,279.32 2093 $22,139,401.03 6.34 $3,490,282.23 2094 $23,910,553.11 6.33 $3,777,058.92 2095 $25,823,397.36 6.32 $4,087,398.43 2096 $27,889,269.15 6.31 $4,423,236.78 2097 $30,120,410.68 6.29 $4,786,669.06 2098 $32,530,043.54 6.28 $5,179,962.51 2099 $35,132,447.02 6.27 $5,605,570.66 2100 $37,943,042.78 6.25 $6,066,148.61 2101 $40,978,486.20 6.24 $6,564,569.63 2102 $44,256,765.10 6.23 $7,103,943.09 Even so, EARTH population DECLINES dramatically to 600 millions; Year Earth Off-world Light Years Stars Density/Star 2051 6.62 0.28 0.33 1 0.276 2052 6.36 0.53 0.67 1 0.527 2053 6.10 0.77 1.00 1 0.768 2054 5.86 1.00 1.33 1 0.998 2055 5.63 1.22 1.67 1 1.219 2056 5.40 1.43 2.00 1 1.430 2057 5.18 1.63 2.33 1 1.633 2058 4.98 1.83 2.67 1 1.826 2059 4.78 2.01 3.00 1 2.012 2060 4.59 2.19 3.33 1 2.189 2061 4.40 2.36 3.67 1 2.359 2062 4.23 2.52 4.00 1 2.522 2063 4.06 2.68 4.33 3 0.892 2064 3.90 2.83 4.67 3 0.942 2065 3.74 2.97 5.00 3 0.990 2066 3.59 3.10 5.33 3 1.035 2067 3.45 3.24 5.67 3 1.078 2068 3.31 3.36 6.00 4 0.840 2069 3.18 3.48 6.33 4 0.870 2070 3.05 3.59 6.67 4 0.898 2071 2.93 3.70 7.00 4 0.925 2072 2.81 3.80 7.33 4 0.951 2073 2.70 3.90 7.67 4 0.976 2074 2.59 4.00 8.00 5 0.800 2075 2.49 4.09 8.33 7 0.584 2076 2.39 4.18 8.67 8 0.522 2077 2.29 4.26 9.00 8 0.532 2078 2.20 4.34 9.33 8 0.542 2079 2.11 4.41 9.67 9 0.490 2080 2.03 4.48 10.00 9 0.498 2081 1.95 4.55 10.33 10 0.455 2082 1.87 4.62 10.67 11 0.420 2083 1.79 4.68 11.00 14 0.334 2084 1.72 4.74 11.33 18 0.263 2085 1.65 4.79 11.67 23 0.208 2086 1.59 4.85 12.00 24 0.202 2087 1.52 4.90 12.33 27 0.181 2088 1.46 4.94 12.67 29 0.170 2089 1.40 4.99 13.00 31 0.161 2090 1.35 5.03 13.33 32 0.157 2091 1.29 5.07 13.67 33 0.154 2092 1.24 5.11 14.00 36 0.142 2093 1.19 5.15 14.33 39 0.132 2094 1.14 5.19 14.67 42 0.123 2095 1.10 5.22 15.00 45 0.116 2096 1.06 5.25 15.33 49 0.107 2097 1.01 5.28 15.67 52 0.101 2098 0.97 5.31 16.00 56 0.095 2099 0.93 5.33 16.33 59 0.090 2100 0.90 5.36 16.67 63 0.085 2101 0.86 5.38 17.00 67 0.081 2102 0.83 5.40 17.33 71 0.076 2103 0.79 5.42 17.67 75 0.072 2104 0.76 5.44 18.00 79 0.069 2105 0.73 5.46 18.33 84 0.065 2106 0.70 5.48 18.67 88 0.062 2107 0.67 5.49 19.00 93 0.059 2108 0.65 5.51 19.33 98 0.056 2109 0.62 5.52 19.67 103 0.053 2110 0.60 5.54 20.00 109 0.051 These stars are from actual surveys out to 20 light years. The important point is that Earth's population in 2110 is still 600 million people - and even though 5.54 billions are off-world, average per star is only 51 millions! So, an aggressive program of expansion beyond Earth would not allow populations to accumulate to a level that would be of military concerns to those remaining on Earth within the solar system. That is, the Earth will continue to militarily dominate interstellar affairs - which should ease the concerns of some who worry about this possibility. Dr. Von Braun actually may have set space colonization back a century by writing his classified PhD thesis for the German high command back in the 1930s. Here he described how someone who had a permanent base on the moon, with self sufficient industrial infrastructure to build rockets could bombard the Earth at will and with this threat and beyond the means of Earth to retaliate (its much harder to go to the moon than return from the moon - look at the size of the Apollo rocket and the LEM) control the world. This analysis also applies to Mars, and development of the asteroids in-situ. Not so much to Venus due to its size, or the outer planets or Mercury, due to the enrgetics and timing of things. vonBraun's analysis fails completely beyond the Sun. The energy and resources it takes to span the distance between the stars is large compared to the success of any military campaign. So, we're safe again - if we can keep control of developments. This is achieved by; (1) capturing rich asteroids and processing them in Earth orbit using telerobotics; (2) using solar pumped lasers to propel spaceships from star to star, and across the solar system, and maintaining control of those lasers; (3) promoting expansion beyond the solar system so no populations accumulate around sol vonBraun's paper remained classified until after 1960s. So, it MUST have figured prominently in the creation of the OST and missile proliferation planning of the era prior to that time. So, this is why I take special care to address this specific concern. Using weapons grade fissile materials to build triggers for fusion pulse spaceships that capture rich asteroids and bringing them into Earth orbit, and raise industrial satellties - to process those asteroids by solar powered tele-operated industry and distributed to everyone on Earth - and allowing everyone on Earth to be employed tele- robotically from anywhere - resolves many of the issues facing humanity today. Including deflecting dangerous asteroids away from Earth or into safe stable orbits. This, along with power satellites, and global wireless hotspot, is the first step along a path that leads to the stars relatively quickly. Building space colonies on orbit from captured asteroids, moving those colonies across the solar system, with solar pumped lasers, orbiting close in to the sun, and then beyond the solar system, using laser light sails, provides a means to move people off-world and out of the solar system to the stars beyond. Even at 1/3 light speed - we have the possibility before the end of the 21st century - of reducing Earth's population to less than 600 millions and the average population per star system to less than 50 millions.
From: William Mook on 7 Feb 2010 14:18 Beyond 2110 - assuming continuous expansion at 1/3 light speed - we reach 200 light year radius in 600 years - in 2650 (we started in 2050 according to the projections). At that point we have the following figures; Number of Stars: 108,808 Number of People: 2.07 billions Which is 19,025 people per star on average and each person . 200 light years is only 1/1,000th the span of the Milky Way! Another point: At 8% economic growth; Wealth: 1e+20 times 2050AD income per capita. Which means each person makes 1 million times more money than the ENTIRE WORLD makes today. Which doesn't seem possible to us here on Earth, but to those surrounded by the resources of the cosmos, and beneficiaries of advanced self-replicating machine systems informed by super-human AI, whatever they can imagine, they will have. Its imagining it that will be the issue - which is far different than the world we face today - where our imaginations are constrained from birth - for our own good! lol. (it is our abject lack of imagination that is causing most of our problems today) As our densities fall, and our population falls, combined with rising living standards we may at the end of the 21st century build upon the successful sequencing of the human genome at the end of the 20th century - by using forensic data - including genetic data gathered from forensic sources - to RE-CREATE people. Since birth rates are below replacement level, and wealth is tremendous, challenges are likely to be tremendous as well. So, re-creating people who have lived before using genetic engineering, will be appealing from a sociology and industrial perspective. Just as ecologies benefit from biological diversity - so too do well functioning societies benefit from social and biological diversity. If we get really good at things, our population will not decline - no one will die - and we will recreate EVERYONE that has lived before - which will put our population - both natural and synthetics - at 19 billions. Artificials (AI) will grow without bound. This may be an area of friction if mismanaged - especially as they get smarter than us. Even so, the fundamentals won't change. Even AI will expand into a very large cosmos and see its population density fall. So, what I'm saying is that even in 600 years we may have 20 billions - of which 18 billions would be synthetics reconstructed from forensic data - 2 billions would be naturals - and likely 2 trillions of super- human AI serving the biologicals - but mostly tending to their own interests after fulfilling their programming. Even in this scenario, in 600 years, there are fewer people PER STAR SYSTEM than live in Dayton Ohio today. As we expand outward, these densities will fall. At some point we will create superluminal travel - which is the same as saying we can travel through time. The simplest way to achieve this is to send a signal or object to the super-massive black hole at the center of our galaxy. If we are lucky, it is spinning fast enough to have time-violating regions -so closed time like loops are possible. This means a signal can be sent to the supermassive black hole and it arrives 30,000 years after being sent. It enters a CTL and emerges 60,000 years before it arrives. It then is broadcast and is received by a radio telescope at a distant star the moment it was sent. A similar arrangement at a distant star allows instant communication. Or communication through time. Replace the signals with spacecraft that move very near the speed of light - and you can travel instantly anywhere. Replace the supermassive black hole at the center of the galaxy with custom built engineered black holes and you can do this more conveniently. Moving anywhere instantly - and anywhen. Where do we get black holes? Shaped masses of iron-56 when collided at 1/3 light speed - can be made to form black holes. You can do this with arrays of solar pumped lasers large enough to drive starships from star to star. Once you have a collection of engineered black holes, it may be possible to cause them to interact in such a way as to cause decay of the vacuum - to create other black holes - a self replicating black hole machine. If that's possible, then we will have created a new class of engineered product. Not one based on crude matter - but one based on charged, spinning, massive points of matter that distort spacetime in controlled ways - and allow creation of time machines which give us instant access across the cosmos to ALL OF SPACE AND TIME! This is likely to happen well before we reach 200 light years from Earth - well before 600 years from the present day. When it happens, if it is possible at all, our densities will drop even faster than reflected in the charts above! That is, if our speed jumps from 1/3 light speed before 2650 to infinity - our range of habitation rises from 108,808 stars within 200 light years of Earth to the 40,000 billion billion star systems in the cosmos - at ANY TIME spanning the 1,000 billion years of interest to intelligence! THIS EXPLAINS THE FERMI PARADOX. Even with 20 billions of us - and 2 trillion super-human AI - there are 20 trillion star systems per person - and a trillion years within each star system to play in. The odds of finding anyone anywhere with this sort of technology - is nearly non-existent - even if everyone everywhere - has this sort of technology.
From: Pat Flannery on 8 Feb 2010 01:38 David Spain wrote: > To William Mook: please ignore this post. > To the rest of the group: ;-) I'm still trying to figure out that wheelbarrow Tony Lance keeps going on about that has the wheel in the wrong place. You had better do some math on that also. Pat
From: William Mook on 12 Feb 2010 16:14 On Dec 18 2009, 4:43 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > "Jonathan" <H...(a)Again.net> wrote in message > > news:p5SdndXFAKoISrfWnZ2dnUVZ_vWdnZ2d(a)giganews.com... > > >I like this idea, Relatively small mirrors would power > > the lasers, not huge solar cell arrays. The lasers would > > transmit their beams to other satellites that convert it to, and > > beam it down, as microwaves. No need for mile-size > > collectors in orbit. > > What are you babbling about? I can't be certain, but I will say that if you move a solar collector array closer to the sun it will gather more energy for a given size. For example, something only 3 million km from the solar center will be 1/50th the distance from the sun as the Earth. So, solar intensity is 2,500x greater than at Earth orbit. That's 3.45 megawatts per square meter. So, to intercept 17 TW of power requires less than 5 square km of area. At 33% overall efficiency that's 15 sq km. Using solar power to sail a power satellite to the sun. Something only 4.4 km in diameter - to power the WHOLE EARTH! A 4.4 km diameter laser emitter is capable of forming a spot less than 41.6 meters across at Earth Orbit using 1,000 nm wavelength light. A 400 meter diameter system (1/10th the diam) produces 170 GW (1/100th the power) and forms a spot reliably 400 meters across (1/10th the angular resolution). 20 of these satellites would power the entire Earth. 10 at sol, 10 at GEO. 25,000 comparably sized satellites would be needed to do it all at GEO. Since we can use sunlight to propel satellites toward the sun fairly efficiently, once they're on orbit, this is something we can consider doing today. 170 GW at $0.043 per kWh generates $7.31 million per hour. That's $64 billion per year. $12.8 trillion over 20 years. Compare this to $2,924 per hour and $25.6 million per year and $512 million over 20 years. The first satellite pays for the entire program to build it from scratch. The second satellite which is the same size and cost barely pays for launch cost.
From: Androcles on 12 Feb 2010 17:16
"William Mook" <mokmedical(a)gmail.com> wrote in message news:fbbddf2d-60ea-4ed3-a183-23e920219728(a)k41g2000yqm.googlegroups.com... On Dec 18 2009, 4:43 am, "Androcles" <Headmas...(a)Hogwarts.physics_q> wrote: > "Jonathan" <H...(a)Again.net> wrote in message > > news:p5SdndXFAKoISrfWnZ2dnUVZ_vWdnZ2d(a)giganews.com... > > >I like this idea, Relatively small mirrors would power > > the lasers, not huge solar cell arrays. The lasers would > > transmit their beams to other satellites that convert it to, and > > beam it down, as microwaves. No need for mile-size > > collectors in orbit. > > What are you babbling about? I can't be certain, but I will say that if you move a solar collector array closer to the sun it will gather more energy for a given size. ============================================= It won't be in Earth orbit then. |