  With the advent of delegated quantum computing as a service, verifying
quantum computations is becoming a question of great importance. Existing
information theoretically Secure Delegated Quantum Computing (SDQC) protocols
require the client to possess the ability to perform either trusted state
preparations or measurements. Whether it is possible to verify universal
quantum computations with information-theoretic security without trusted
preparations or measurements was an open question so far. In this paper, we
settle this question in the affirmative by presenting a modular, composable,
and efficient way to turn known verification schemes into protocols that rely
only on trusted gates.
  Our first contribution is an extremely lightweight reduction of the problem
of quantum verification for BQP to the trusted application of single-qubit
rotations around the Z axis and bit flips. The second construction presented in
this work shows that it is generally possible to information-theoretically
verify arbitrary quantum computations with quantum output without trusted
preparations or measurements. However, this second protocol requires the
verifier to perform multi-qubit gates on a register whose size is independent
of the size of the delegated computation.
