The reaction e(+)p --> e(+)X is studied with the H1 detector at HERA. The d
ata cover momentum transfers Q(2) between 200 GeV2 and 30 000 GeV2 and corr
espond to an integrated luminosity of 35.6 pb(-1). The differential cross s
ection d sigma/dQ(2) is compared to the Standard Model expectation for neut
ral current scattering and analysed to search for ((e) over bar e)((q) over
bar q) contact interactions. No evidence for new phenomena is observed. Th
e results are used to set limits on scales within models of electron-quark
compositeness, quark form factors and the exchange of virtual heavy leptoqu
arks. A search for gravitational effects mediated through the exchange of v
irtual gravitons which propagate into large extra dimensions is presented.
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