According to the theory of relativity, no information can travel faster than the speed of light in vacuum, but this does not mean that the refractive index cannot be lower than 1. The refractive index measures the phase velocity of light, which does not carry information. The phase velocity is the speed at which the crests of the wave move and can be faster than the speed of light in vacuum, and thereby give a refractive index below 1. This can occur close to resonance frequencies, for absorbing media, in plasmas, and for X-rays. In the X-ray regime the refractive indices are lower than but very close to 1 (exceptions close to some resonance frequencies). As an example, water has a refractive index of 6999999999740000000♠️0.99999974 = 1 6993260000000000000♠️2.610 for X-ray radiation at a photon energy of 6985480652946099999♠️30 keV (0.04 nm wavelength).
can a refractive index be less than 1?
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Answer: yes

A sovereign default (/svrn/) is the failure or refusal of the government of a sovereign state to pay back its debt in full. Cessation of due payments (or receivables) may either be accompanied by formal declaration (repudiation) of a government not to pay (or only partially pay) its debts, or it may be unannounced. A credit rating agency will take into account in its gradings capital, interest, extraneous and procedural defaults, failures to abide by the terms of bonds or other debt instruments. Countries have at times escaped the real burden of some of their debt through inflation. This is not ''default'' in the usual sense because the debt is honored, albeit with currency of lesser real value. Sometimes governments devalue their currency. This can be done by printing more money to apply toward their own debts, or by ending or altering the convertibility of their currencies into precious metals or foreign currency at fixed rates. Harder to quantify than an interest or capital default, this often is defined as an extraneous or procedural default (breach) of terms of the contracts or other instruments.
can a country refuse to pay its debt?
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Answer: yes

Beginning November 1, 2011, it is legal to load a handgun, or to transport a loaded handgun cased or uncased, in a vehicle without a license. NOTE: This does NOT apply to long guns; they still must be unloaded, but now may be uncased. There is still some confusion as to whether or not an encased gun is concealed, so if it is cased, best practice is to keep the long gun out of reach. Long guns must be ''discernable to ordinary observation'', since a conceal carry license does not apply. Previously all firearms had to be unloaded & encased (per the transport statute), & out of reach (derived from the concealed carry statute). Those with a concealed carry license may conceal a pistol in a vehicle.
can you carry a gun in your car in wisconsin?
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Answer:
yes