All posts by Peter Rohde
The island of Telendos






























3 Stripes route — Kalymnos, Greece
A general framework for the composition of quantum homomorphic encryption & quantum error correctionÂ
A new paper on the arXiv with Yingkai Ouyang on composing quantum homomorphic encryption with quantum error correction, necessary for large-scale, secure, cloud quantum computing.
Abstract: Two essential primitives for universal, cloud-based quantum computation with security based on the laws of quantum mechanics, are quantum homomorphic encryption with information-theoretic security and quantum error correction. The former enables information-theoretic security of outsourced quantum computation, while the latter allows reliable and scalable quantum computations in the presence of errors. Previously these ingredients have been considered in isolation from one another. By establishing group-theoretic requirements that these two ingredients must satisfy, we provide a general framework for composing them. Namely, a quantum homomorphic encryption scheme enhanced with quantum error correction can directly inherit its properties from its constituent quantum homomorphic encryption and quantum error correction schemes. We apply our framework to both discrete- and continuous-variable models for quantum computation, such as Pauli-key and permutation-key encryptions in the qubit model, and displacement-key encryptions in a continuous-variable model based on Gottesman-Kitaev-Preskill codes.
Regensburg route — Kalymnos, Greece
Ferrata route — Kalymnos, Greece
MoodSnap! Technology for mental health Â
In this article published in The Spectator, I discuss the importance of incorporating mental health into digital health ecosystems like Apple Health, Google Fit and Fitbit. Mental health is as important as physical health, and the two are intimately connected. It would be remiss for digital health ecosystems to overlook this important aspect of our wellbeing.
Featuring in the article is my new open-source project MoodSnap for realtime tracking of mental health.
Sydney sunsets














Sydney from a distance














MoodSnap adds Apple Health dataÂ
The new MoodSnap v1.1 now optionally incorporates your Apple Health data to correlate your mood with sleep, weight, active energy, walking & running distance, and menstrual cycle. HealthKit integration can be enabled under Settings.
You can download MoodSnap here.