This paper reviews the physical state of stars and Interstellar Matter in the Galactic Bulge (radius$R sim 0.3 - 3,$kpc from the dynamical center of the Galaxy), in the Nuclear Bulge ($R < 0.3,$kpc) and in the Sgr A Radio and GMC Complex, i.e. the central$sim 50$,pc of our Galaxy. The Galactic Bulge is devoid of cold Interstellar Matter and consists mainly of old stars, while the Nuclear Bulge accounts for$sim 10,%$of the mass of all of the Interstellar Matter in the Galaxy. A similar ratio holds for the formation rate of medium and high mass stars in Bulge and Disk. The metal abundance of the Interstellar Matter in the Galactic Bulge is found to be$left Z/Z_odotright sim 2$. The H$_2$-to-$^{12}$CO conversion factors to be applied to molecular gas in the Central Region are by factors 3 (Arimoto et al. 1996) to 10 (Sodroski et al. 1995) lower than in the solar vicinity. Hence, most H$_2$masses derived for the Central Region appear to be considerably overestimated. The Nuclear Bulge is pervaded by a thermal plasma ($T_{rm e} le 7000,$K) which is responsible for the diffuse free-free emission. Lyman continuum photon and dust IR luminosity of the Nuclear Bulge again account for$sim 10,%$of the respective total luminosities of the Galaxy. Magnetic fields in the Nuclear Bulge are strong (up to$sim 2,$mG) as compared with the Galactic Disk (a few tens of$mu$G). The field lines are oriented parallel to the galactic plane inside giant molecular clouds and perpendicular to the plane in the intercloud medium. The compact source Sgr A* is close to or at the dynamical center of the Galaxy. Its radio spectrum with a high frequency cut-off at$nu_{rm c} sim 2000 - 4000,$GHz, a low frequency turnover at$nu sim 0.8,$GHz and a$S_nu propto nu^{1/3}$flux density dependence in between can be explained by synchrotron emission from quasi-monoenergetic relativistic electrons. Due to an extinction between Sun and Galactic Center corresponding to$A_{rm V} sim 31^{rm m}$, an intrinsic weakness of this source in the near infrared, and a strong background emission from warm dust there are only upper limits available for the flux density of Sgr A* in the far, mid and near infrared and X-ray regime. The size of Sgr A* in the radio regime is$le 2.5 -4,10^{13},$cm, its dereddened K-band flux density is$< 9,$mJy, its luminosity has upper limits of$le 10^3,{rm L}_odot$(if radiation comes from an Accretion Disk) and$le 5,10^4,{rm L}_odot$(if black-body radiation from an object with a single temperature of$sim 4,10^4,$K is assumed). If anyone of the soft X-ray sources detected by ROSAT actually coincides with Sgr A*, its X-ray luminosity would be less than a few$10^2,{rm L}_odot$. With a dark mass of$sim 2 - 3,10^6,{rm M}_odot$Sgr A* is the best candidate for a starving black hole, although there are no observational indications for the presence of a (Standard) Accretion Disk. While the radio/IR spectrum of Sgr A* is purely nonthermal, the spectrum integrated over the central parsec resembles that of a Seyfert galaxy. Sgr A* is embedded in the Hiiregion Sgr A West with part of the ionized gas forming a minispiral. Sgr A West is surrounded by the Circum Nuclear Disk, an irregular shaped assembly of$sim 10^4,{rm M}_odot$molecular gas which extends from$R sim 1.7 - 7,$pc and rotates around the Galactic Center with an estimated dynamical time scale of$sim 10^5$,yr. The total luminosity of$sim 10^8,{rm L}_odot$of the central parsec is due to the radiation of early-type stars of which$sim 24$have now been directly identified as luminous blue supergiants. It is still debated, however, if these stars can also account for all of the ionization of Sgr A West. In addition, the central parsec contains red giants, AGB stars, and a few super giants of which the brightest$sim 500$are now identified by direct imaging. These stars – together with a few million low mass main sequence stars – account for the bulk of the 2.2,$mu$m emission. The spatial distributions of the three stellar populations in the central$sim 1 - 2,$pc are remarkably different. Sgr A* is – along the line-of-sight – presumably located close to the center of the Hiiregion Sgr A West, which in turn is located in front of the extended ($sim 10,$pc) synchrotron source Sgr A East, which appears to be the remnant of a gigantic explosion (of the order of$sim 40times$the energy of a single supernova explosion) which took place$sim 5,10^4,$yr ago inside the GMC Sgr A East Core. X-ray observations show within$pm 80,$pc a pervasive hot ($kT sim 10,$keV) plasma of expansion age of$sim 10^5,$yr. Both phenomena – as well as the formation of the Circum Nuclear Disk – may have the same origin. Influx of material is observed within the Nuclear Bulge on all distance scales. In the Nuclear Bulge ($R le 200,$pc) as well as in the Circum Nuclear Disk ($R le 7,$pc) inflow towards the Galactic Center occurs primarily in the galactic plane and amounts to a few$10^{-2},{rm M}_odot,{rm yr}^{-1}$. The accretion rate into the central Black Hole, deduced from the luminosity of Sgr A*, however, appears to be lower by at least five orders of magnitude (assuming standard disk accretion). But in an equilibrium state only part of the infalling mass which is not accreted by the Black Hole can be consumed by star formation. A mass inflow rate varying with time is a more natural explanation. Comparing the physical state of the Center of our Galaxy with that of Active Galactic Nuclei derived from observations and modelling, we find that most of the basic characteristics of an AGN are also present in the Galactic Center. Lacking are, however, both the evidence for a standard Accretion Disk and a hard UV spectrum with accompanying high excitation emission lines in the Galactic Center which are characteristic for AGN. The luminosity of the central parsec,$sim 10^8,{rm L}_odot$, amounts to only$sim 0.3,%$of the total luminosity of the Galaxy of$sim 4,10^{rm 10},{rm L}_odot$. Seen from a distance of M31 ($D sim 700,$kpc) with an angular resolution of$sim 0.!!^{primeprime} 5$(corresponding to a linear size of$sim 1,$pc) the Center of our Galaxy would appear as a mildly active nucleus with some starburst activity and would probably be classified as a weak Seyfert galaxy. The synchrotron spectrum of Sgr A*, however, would be completely masked by reprocessed stellar light (i.e. free-free and dus
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