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mathematics - 2017-03-19T17:26:44Z ago
Evolutionary theories defined
A gene can be expressed at various stages of life. Therefore, natural selection can support lethal and harmful alleles, if their expression occurs after reproduction. Senescence may be the product of such selection.[25][26][27] In addition, ageing is believed to have evolved because of the... Read more
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mathematics - 2017-03-19T17:26:44Z ago
The problem of finding the ultimate core model defined
The problem of finding the ultimate core model, one that contains all large cardinals.
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mathematics - 2017-03-19T17:26:44Z ago
prime quadruplets divided 1 subproblem
Are there infinitely many prime quadruplets?
mathematics - 2017-03-19T17:26:44Z ago
Chvátals toughness conjecture defined
that there is a number t such that every t-tough graph is Hamiltonian
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mathematics - 2017-03-19T17:26:44Z ago
Lyapunovs second method for stability defined
For what classes of ODEs, describing dynamical systems, does the Lyapunov’s second method formulated in the classical and canonically generalized forms define the necessary and sufficient conditions for the (asymptotical) stability of motion?
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mathematics - 2017-03-19T17:26:44Z ago
Furstenberg conjecture defined
Is every invariant and ergodic measure for the x2, x3 action on the circle either Lebesgue or atomic?
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mathematics - 2017-03-19T17:26:44Z ago
Pentagonal tiling defined
15 types of convex pentagons are known to monohedrally tile the plane, and it is not known whether this list is complete
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mathematics - 2017-03-19T17:26:44Z ago
The einstein problem defined
Is there a two-dimensional shape that forms the prototile for an aperiodic tiling, but not for any periodic tiling?
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chemistry - 2017-03-19T17:26:44Z ago
nature of strong gold-chalcogens in thiols defined
What is the nature of strong gold-chalcogens in thiols and other organochalcogens (i.e., sulfur and higher chalcogen-containing organic compounds)?
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chemistry - 2017-03-19T17:26:44Z ago
alpha effect defined
What is the origin of the alpha effect, that is, that nucleophiles with an electronegative atom with lone pairs adjacent to the nucleophilic center are particularly reactive?
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chemistry - 2017-03-19T17:26:44Z ago
chirality defined
Is an abiologic origin of chirality as is found in (2R)-2,3-dihydroxypropanal (D-glyceraldehyde), and also in amino acids, sugars, etc., possible?
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organic chemistry - 2017-03-19T17:26:44Z ago
electromagnetic energy to chemical energy defined
How can electromagnetic energy (photons) be efficiently converted to chemical energy? For instance, can water be efficiently split to hydrogen and oxygen using solar energy?[3][4]
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chemistry - 2017-03-19T17:26:44Z ago
Neutronium-4 defined
Neutronium-4
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chemistry - 2017-03-19T17:26:44Z ago
Feynmanium defined
Is Feynmanium the last chemical element that can physically exist? That is, what are the chemical consequences of having an element with an atomic number above 137, whose 1s electrons must travel faster than the speed of light?[1][2]
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chemistry - 2017-03-19T17:26:44Z ago
high temperature superconductors defined
What are the electronic structures of high-temperature superconductors at various points on their phase diagrams?
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